US – Egypt ASI
US – Egypt science and Technology Institute
"Nanomaterials and Nanocatalysis for Energy, Petrochemicals and Environmental Applications" National Research Centre Cairo, March 27 – April 5
under the auspices of
Prof . Dr. Ashraf Shaalan President, National Research Centre
Organized by
Prof. Dr. Mohamed S. El-Shall
Dr. Mostafa A. El-Sayed
Prof. of Chemistry Virginia Commonwealth University Richmond, Virginia, USA
Julius Brown Chair and Regents Professor Georgia Institute of Technology Atlanta, Georgia, USA
Prof. Dr. Ali Ali Shabaka Professor of Spectroscopy, Physics Division, National Research Centre, Cairo, Egypt
Egyptian scientific and organizing committee (Alphabetical order)
Ali Ali Shabaka Professor of Spectroscopy, Physics Division, National Research Centre, Cairo, Egypt
Ayman Mohamady Head of Special Application, Egyptian Petroleum Research Institute (EPRI), Cairo, Egypt
Hassan Talaat Professor of Physics, Faculty of Science, Ain Shams University, Cairo, Egypt
Mahmoud Zawra Head of Center of Excellence for Advanced Sciences, National Research Centre, Cairo, Egypt
Mona Bakr Professor in National Institute of Laser Enhanced Science (NILES) Cairo University, Giza, Egypt
Yassir Mostafa Vice Director of Central Analytical of Egyptian Petroleum Research Institute (EPRI), Cairo, Egypt
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First Day Sunday, March 28, 2010 National Research Centre, Cairo 9:00 – 10:00
Registration
10:00 – 11:00
Opening Session
10:00 - 10:15
Prof. Dr. Samy El-Shall ASI Chairman & US Organizer Virginia Commonwealth University, USA Prof. Dr. Mostafa El-Sayed US Co-Organizer Georgia Institute of Technology, USA Margaret Scobey Her Excellency USA Ambassador to Egypt Prof. Dr. Ashraf Shaalan President, National Research Centre
10:15 – 10:30 10:30 – 10:40 10:40 – 10:50 11:00 – 11:30
Coffee Break
11:30 – 13:30
PLENARY SESSION-1 NANOMATERIALS & CATALYSIS Chairpersons: Lotfia El Nadi (Egypt) & Samy El-Shall (USA)
11:30 – 12:30
The Use of the Nanoscale Confinement Properties of Nanoparticles in Some Applications to Environmental, Catalytic and Energy Research Mostafa El-Sayed Georgia Institute of Technology Atlanta, GA 30332-0245, USA
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12:30 – 13:30
Catalysis from Single Crystals to Nanoparticles & Energy Applications D. Wayne Goodman Texas A&M University College Station, TX 77842-3012, USA
13:30 – 14:45
Lunch
14:45 – 16:45
PLENARY SESSION-2 NANOMATERIALS & SOLAR CELLS Chairpersons: Mostafa El-Sayed (USA) & Ahmed Galal (Egypt)
14:45 – 15:45
Nanostructure Nanoassemblies for Next Generation Solar Cells Prashant V. Kamat University of Notre Dame Notre Dame, Indiana 46556-0579, USA
15:45 – 16:45
The Rise of Graphene: Catalysis & Nanocomposite Applications M. Samy El-Shall Virginia Commonwealth University Richmond, VA 23284-2006, USA
17:00
Bus to Old Cairo & Khan Al Khalili
19:30 – 21:30
Dinner at Naguib Mahfouz Restaurant
21:30
Bus to Swiss Inn Pyramids Resort
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Day 2 Monday, March 29, 2010 Hilton Pyramids Golf Resort Dreamland, El Wahat Road, 6th of October City, Egypt 2500
9:00 – 11:00
SESSION-3 FUNDAMENTALS OF NANOCATALYSIS-1 Chairpersons: Wayne Goodman (USA) & Mohammed Ibrahim Zaki (Egypt)
9:00 – 10:00
Fundamentals of Surface Reactions & Mechanisms Francisco Zaera University of California at Riverside Riverside, CA 92521, USA
10:00 – 11:00
Tutorial for Characterizing Catalysts using Probe Molecules Mark G. White Mississippi State University Mississippi State, MS 39762-9595, USA
11:00 – 11:30
Coffee Break
11:30 – 13:30
SESSION-4 FUNDAMENTALS OF NANOCATALYSIS-2 Chairpersons: Francisco Zaera (USA) & Hassan Talaat (Egypt)
11:30 – 12:30
Supported Metal Clusters: Spectroscopic and Microscopic Evidence of Synthesis, Structure, Reactivity, and Catalysis Bruce Gates University of California at Davis Davis, CA 95616, USA
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12:30 – 13:30
Nanostructured Surfaces for Sensing and Catalysis Applications Ahmed Galal Faculty of Science, University of Cairo Giza 12613, Egypt
13:30 – 15:00
Lunch
16:00 – 18:00
SESSION-5 FUNDAMENTALS OF NANOCATALYSIS-3 Chairpersons: Mark White (USA) & Abd El-Aziz M. Saeed (Egypt)
16:00 – 17:00
Observation of Chemical Reactions on Surfaces using STM. Watching Individual Molecules do their Molecular Dances John T Yates, Jr. University of Virginia Charlottesville, VA 22904, USA
17:00 – 18:00
Surface Enhanced Raman Spectroscopy as Nanoscience Hassan Talaat Faculty of Science, Ain Shams University Cairo, Egypt
18:30 – 20:00
Dinner
20:00 – 22:00
Poster Session I
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Day 3 Tuesday, March 30, 2010 Hilton Pyramids Golf Resort
9:00 – 11:00
SESSION-6 SUPPORTED METAL OXIDES Chairpersons: Mohamed Eddaoudi (USA) & Ahmed Abd El-Menniem (Egypt)
9:00 – 10:00
Synthesis and Characterization of Highly-Dispersed, Supported Metal Oxide Catalysts Mark G. White Mississippi State University Mississippi State, MS 39762-9595, USA
10:00 – 11:00
Selective Oxidation of Methanol to Formaldehyde over Molybdenum Oxide Supported on NanoHydroxyapatite Catalysts Abd El-Aziz Mohamed Said Faculty of Science, Assiut University Assiut, Egypt
11:00 – 11:30
Coffee Break
11:30 – 13:30
SESSION-7 NATURAL GAS & WATER-GAS SHIFT Chairpersons: Mohammed Ibrahim Zaki (Egypt) Mark White (USA) &
11:30 – 12:30
12:30 – 13:30
Oxidative Coupling of Natural Gas using Nano-Membrane Technology Magdy M. Nasrallah Department of Petroleum and Energy Engineering The American University in Cairo Cairo, Egypt Recent Developments in the Application of
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Nanoparticles of Differently Prepared Modified Metal Gold / Supported Catalysts for the Water Gas Shift Activity Rabee Gabr Faculty of Science, Assiut University Assiut, Egypt 13:30 – 15:00
Lunch
16:00 – 18:00
SESSION-8 PETROCHEMICAL CATALYSIS Chairpersons: Samy El-Shall (USA) & Magdi M. Nasralla (Egypt)
16:00 – 17:00
Petrochemicals Processing: Past Experience and Future Prospects Mohammed Elsokkary Egyptian Petroleum Research Institute (EPRI) Cairo, Egypt
17:00 – 18:00
A View on Catalysis in the Process Development Department in EPRI Kadri Abu El-Gheit Egyptian Petroleum Research Institute (EPRI) Cairo, Egypt
18:30 – 20:00
Dinner
20:00 – 21:00
Ethics of Scientific Publication: How to Write an Effective Scientific Paper Prashant V. Kamat University of Notre Dame Notre Dame, Indiana 46556-0579, USA
21:00 – 22:00
Round Table Discussion
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Day 4 Wednesday, March 31, 2010 Hilton Pyramids Golf Resort
9:00 – 11:00
SESSION-9 NANOMATERIALS FOR ENERGY & ENVIRONMENT-1 Chairpersons: Puru Jena (USA) & Mona M. Bakr (Egypt)
9:00 – 10:00
Carbon Nanostructures for Energy Conversion Prashant V. Kamat University of Notre Dame Notre Dame, Indiana 46556-0579, USA
10:00 –11:00
Effect of Preparation Parameters on the Properties of TiO2 Nanoparticles for Dye Sensitized Solar Cells Abd El-Hady Besheir Kashyout Mubarak City for Scientific Research & Technology Applications Burg El-Arab, Alexandria, Egypt
11:00 – 11:30
Coffee Break SESSION-10 NANOMATERIALS FOR ENERGY & ENVIRONMENT-2 Chairpersons: Bruce Gates (USA) & Kadri Abu El-Gheit (Egypt)
11:30 – 12:30
Nanomaterials in Environmental Processes Vicki Grassian University of Iowa Iowa City, IA 52242-1294, USA
12:30 – 13:30
Fundamental Aspects of Photochemistry on TiO2
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Surfaces-Using Sunlight for Environmental Remediation John T Yates, Jr. University of Virginia Charlottesville, VA 22904, USA 13:30 – 15:00
Lunch
16:00 – 18:00
SESSION-11 NANOMATERIALS FOR ENERGY APPLICATIONS Chairpersons: John Yates (USA) & Abd El-Hady B. Kashyout (Egypt)
16:00 – 17:00
Plasmonic-Semiconductor Hybrid Nanostructures for Photo-Electronic Device Fabrication Mona Bakr Mohamed National Institute of Laser Enhanced Science Cairo University, Giza, Egypt
17:00 – 18:00
Design and In-situ Measurements of Catalytic Conversion and Electrochemical-Energy-Storage Materials: A Bright Future for Synchrotron-based Energy Science Faisal M. Alamgir Georgia Institute of Technology Atlanta, GA 30332-0245, USA
18:30 – 20:00
Dinner
20:00 – 22:00
Poster Session II
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Day 5 Thursday, April 1, 2010 Hilton Pyramids Golf Resort
9:00 – 11:00
SESSION-12 GOLD-BASED NANOCATALYSTS Chairpersons: Samy El-Shall (USA) & Mona Bakr (Egypt)
9:00 – 10:00
Confining Resonant Photons to the Nano-Gold Length Scale: The New Properties and Applications in Material Science, Nanobiology and Cancer NanoMedicine Mostafa El-Sayed Georgia Institute of Technology Atlanta, GA 30332-0245, USA
10:00 – 11:00
Catalysis by Nanosized Gold: The Nature of the Active Site D. Wayne Goodman Texas A&M University College Station, TX 77842-3012, USA
11:00 – 11:30
ASI Formal Group Photo Coffee Break SESSION-13 IR CATALYSIS STUDIES Chairpersons: Vicki Grassian (USA) & Mahmoud Khedr (Egypt)
11:30 – 12:30
Infrared Studies of Interest to Catalysis and Microelectronics
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Francisco Zaera University of California at Riverside Riverside, CA 92521, USA 12:30 – 13:30
IR Observation of Adsorptive and Catalytic Interactions on Metal and Metal Oxide Surfaces Mohammed Ibrahim Zaki Faculty of Science, El Menia University El Menia, Egypt
13:30 – 15:00
Lunch
16:00 – 18:00
SESSION-14 PLASMONIC & HYBRID NANOSTRUCTURED MATERILAS Chairpersons: Francisco Zaera (USA) & Hassan Talaat (Egypt)
16:00 – 17:00
Laser Vaporization Controlled Condensation for the Synthesis of Supported Nanoparticle Catalysts, Nanoalloys & Up-Converting Nanoparticles M. Samy El-Shall Virginia Commonwealth University Richmond, VA 23284-2006, USA
17:00 – 18:00
An Integrated Approach using Spectroscopy, Microscopy and Particle Sizing Methods to Investigate Chemistry on the Nanoscale Vicki Grassian University of Iowa Iowa City, IA 52242-1294, USA
19:00 – 21:00
Sound & Light Show by the Pyramids
21:00 – 22:00
Dinner
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Day 6 Friday, April 2, 2010 Full Day Excursion
9:00
Bus to Sakkara
11:00
Pyramids
12:00
Lunch at the Pyramids
13:00
Egyptian Museum
17:30
Gizyra & Nile Area
19:00
Dinner in Al Saraya Boat
21:00
Bus to Swiss Inn Pyramids Resort
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Day 7 Saturday, April 3, 2010 Hilton Pyramids Golf Resort
9:00 – 11:00
SESSION-15 DESIGN & SYNTHESIS OF NANOMATERIALS FOR ENERGY APPLICATIONS Chairpersons: Lotfia El Nadi (Egypt) & Joseph Francisco (USA)
9:00 – 10:15
Design of Nanomaterials for Energy Applications Puru Jena Virginia Commonwealth University Richmond, VA 23284, USA
10:15 – 11:00
Synthesis, Characterization and Evaluation of New Materials for Hydrogen Storage Nahla Isamil National Research Centre Cairo, Egypt
11:00 – 11:30
Coffee Break
11:30 – 13:15
SESSION-16 HIGH SURFACE AREA MATERIALS Chairpersons: Prashant Kamat (USA) & Nahla Isamil (Egypt)
11:30 – 12:30
Metal-Organic Materials: Strategies toward Functional Porous Materials Mohamed Eddaoudi The University of South Florida Tampa, Florida, 33620, USA
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12:30 – 13:15
Acid Catalyzed Organic Transformations by Heteropoly Tungstophosphoric Acid Supported on MCM-41 and MIL-101 Abd Elrahman Khedr El- Mansoura University El-Mansoura, Egypt
13:15 – 14:45
Lunch
15:30 – 18:00
SESSION-17 ATMOSPHERIC & ENVIRONMENTAL CATALYSIS Chairpersons: Puru Jena (USA) & Ahmed Galal (Egypt)
15:30 – 16:30
Atmospheric Processes on Aerosol and Cloud Surface Joseph S. Francisco Purdue University West Lafayette, Indiana, USA
16:30 – 17:15
Nanocatalysts for CO Oxidation on Different Supports: Mesopourous MCM-41, MIL-101 & Mixed Metal Oxides Hassan M. Ahmed Hassan Suez Canal University Suez, Egypt
17:15 – 18:00
New Nano-Crystalline Electrode Materials for Green Hydrogen Fuel Production from Seawater Electrolysis Ahmed Abd El-Menniem German University in Cairo Cairo, Egypt
18:30 – 20:00
Dinner
20:00 – 21:30
Round Table Discussion Samy El-Shall & Mostafa El-Sayed ASI Evaluation
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Day 8 Sunday, April 4, 2010 Hilton Pyramids Golf Resort
9:00 – 10:45
SESSION-18 CARBON NANOTUBES Chairpersons: Osama Fouad (Egypt) & Faisal Alamgir (USA)
9:00 – 10:00
Metallic and Bimetallic Nanocatalysts for the Economic Synthesis of Decorated Carbon Nanotubes (CNT) for Environmental Applications Mahmoud H. Khedr Faculty of Science, Benisuef university Benisuef, Egypt
10:00 – 10:45
Heating and Cooling Dynamics of Carbon Nanotubes Observed by Temperature-Jump Spectroscopy and Electron Microscopy Omar F. Mohammed Arthur Amos Noyes Laboratory of Chemical Physics California Institute of Technology Pasadena CA 91125, USA
11:30
Bus to NRC Boxed Lunch on the Bus
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Day 8 Sunday, April 4, 2010 International Collaboration & ASI Conclusions National Research Centre, Cairo 13:00 – 15:00
SESSION-19 INTERNATIONAL COLLABORATION Chairperson: Samy El-Shall
13:00 – 14:00
Funding Opportunities in International Collaborations for Materials Research and Education Zakya Kafafi Director, Division of Materials Research (DMR) National Science Foundation (NSF) Arlington, VA 22230, USA
14:00 – 15:00
Overview of the American Chemical Society and U.S. efforts to celebrate the International Year of Chemistry 2011 Joseph S. Francisco President American Chemical Society
15:00 – 15:30
Coffee Break
15:30 – 16:30
SESSION-20 CONCLUSIONS & OUTLOOK Chairperson: Mostafa El-Sayed
15:30 – 16:00
ASI Conclusions Samy El-Shall
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16:00 – 16:30
Closing Remarks Professor Ashraf Shaalan President National Research Centre
17:00
Bus to Nile Cruise
18:00
Nile Cruise Farewell Dinner
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ABSTRACTS
First Day Sunday, March 28, 2010
PLENARY SESSION-1 NANOMATERIALS & CATALYSIS 11:30 – 13:30
Lecture 1 The Use of the Nanoscale Confinement Properties of Nanoparticles in Some Applications to Environmental, Catalytic and Energy Research Mostafa El-Sayed Lecture 2 Catalysis from Single Crystals to Nanoparticles & Energy Applications D. Wayne Goodman
PLENARY SESSION-2 NANOMATERIALS & SOLAR CELLS 14:45 – 16:45
Lecture 1 Nanostructure Nanoassemblies for Next Generation Solar Cells Prashant V. Kamat Lecture 2 The Rise of Graphene: Catalysis & Nanocomposite Applications M. Samy El-Shall
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Sunday March 28, 2010; 11:30
The Use of the Nanoscale Confinement Properties of Nanoparticles in Some Applications to Environmental, Catalytic and Energy Research Mostafa A. El-Sayed Laser Dynamics Laboratory, Georgia Institute of Technology Atlanta, GA 30332-0245, USA E-mail:
[email protected] Reducing the size of material to the nanometer scale confines the motion of its electrons (as in quantum dots used in Bio-labeling) ,the reactants in a chemical reaction which enhances reaction rates (as in nano-reactors), the phonons which heats up and speeds up reaction rates and photons which enhances the electro-magnetic fields of plasmonic gold and silver nano-particles The potential use of these new nano-properties are discussed in the catalytic destruction of some pollutants, in reducing the activation energy in catalysis and in the plasmonic enhancements of the radiative properties of bio-intermediates useful in solar energy conversion by the bacterio-rhodopsin photo-synthetic system.
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Sunday March 28, 2010; 12:30
Catalysis from Single Crystals to Nanoparticles & Energy Applications D. W. Goodman Department of Chemistry, Texas A&M University College Station, TX 77842-3012, USA E-mail:
[email protected] The electronic, structural, and chemical properties of unsupported mixed-metal surfaces prepared either as single crystals or thin films have been detailed and contrasted with the corresponding properties of supported mixed-metal nanoclusters. The latter vary in size from a few atoms to many and have been prepared on ultrathin single crystalline oxide supports of TiO2, Al2O3, and SiO2. An array of surface techniques including reaction kinetics of vinyl acetate synthesis have been used to correlate catalytic function of these surfaces with their physical and electronic properties. Recent studies of mixed-metal catalysts prepared by alloying Pd with Au will be highlighted [1-7]. Thin film Pt-Co alloy electrocatalysts have been characterized using low energy ion scattering spectroscopy (LEISS), X-Ray photoelectron spectroscopy (XPS), low energy electron diffraction (LEED), temperature programmed desorption (TPD), and electrochemical measurements. This combined approach is used to correlate the electrocatalytic activity of Pt-Co toward the oxygen reduction reaction (ORR) with the surface properties of the catalyst before and after the electrochemical measurements. LEISS shows that Pt-Co films form a stable and well-ordered alloy at the outmost layer when annealed to sufficiently high temperatures. The surface phase diagram of co-deposited Pt-Co films shows preferential Pt segregation to the surface. Based on the open-circuit cell potential (OCP) in an O2-saturated sulfuric acid electrolyte, Pt3Co thin films exhibit the highest OCP compared to other Pt-Co bulk compositions. A limited amount of Co was dissolved immediately upon exposure to an electrochemical environment and the fraction stripped was found to be dependent of the applied potential. References 1. 2. 3. 4. 5. 6.
M. S. Chen and D. W. Goodman, Science, 306, 252 (2004). M. S. Chen and D. W. Goodman, Accts Chem. Res, 39, 739 (2006). M. S. Chen, D. Kumar, C.-W. Yi and D. W. Goodman, Science, 310, 291 (2005). M. S. Chen, Y. Cai, Z. Yan and D. W. Goodman, J. Amer. Chem. Soc., 128, 6341(2006). C. W. Yi, K. Luo, T. Wei and D. W. Goodman, J. Phys. Chem. B, 109, 18535 (2005). P. Han, S. Axnanda, I. Lyubinetsky, and D. W. Goodman, J. Am. Chem. Soc., 129, 14355 (2007). 7. F. Gao, Y. Wang, and D. W. Goodman, J. Am. Chem. Soc., 131, 5734 (2009).
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Sunday March 28, 2010; 14:45
Nanostructure Nanoassemblies for Next Generation Solar Cells Prashant V. Kamat Department of Chemistry and Biochemistry, Department of Chemical and Biomolecular Engineering, and Radiation Laboratory, University of Notre Dame, Notre Dame, IN 46556 E-mail:
[email protected] Environmentally friendly energy resources are needed to meet our clean energy demand. Semiconductor nanoparticle and nanotube assemblies provide new ways to develop next generation solar cells.[1-4]. Of particular interest is the nanowire/nanotube architecture which can significantly improve the efficiency of nanostructure based solar cells. We have now developed quantum dot solar cells by assembling different size CdSe quantum dots on TiO2 films composed of particle and nanotube morphologies (Scheme 1). Upon bandgap excitation, CdSe quantum dots inject electrons into TiO2 nanoparticles and nanotubes, thus enabling the generation of photocurrent in a photoelectrochemical solar cell. These composite semiconductor nanostructures can be tailored to tune the photoelectrochemical response via size control of CdSe quantum dots and improve the photoconversion efficiency by facilitating the charge transport through TiO2 nanotube architecture. Ways to improve power conversion efficiency and maximize the light harvesting capability through the construction of a rainbow solar cell and carbon nanotube-semiconductor hybrid assemblies will be presented. The salient features of carbon nanotube and graphene scaffolds [5, 6] for facilitating charge collection and charge transport will also be discussed.
Scheme1. CdSe quantum dots linked to (a) TiO2 nanoparticle and (b) TiO2 nanotube films. (c) Energy level diagram depicting electron injection from CdSe quantum dots into TiO2. References 1. Kamat, P. V., Quantum Dot Solar Cells. Semiconductor Nanocrystals as Light Harvesters. J. Phys. Chem. C, 2008, 112, 18737-18753.
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2. Kongkanand, A.; Tvrdy, K.; Takechi, K.; Kuno, M. K.; Kamat, P. V., Quantum Dot Solar Cells. Tuning Photoresponse through Size and Shape Control of CdSe-TiO2 Architecture. J. Am. Chem. Soc., 2008, 130, 4007-4015. 3. Farrow, B.; Kamat, P. V., CdSe Quantum Dot Sensitized Solar Cells. Shuttling Electrons through Stacked Carbon Nanocups J. Am. Chem. Soc, 2009, 131, 11124-11131. 4. Brown, P.; Kamat, P. V., Quantum Dot Solar Cells. Electrophoretic Deposition of CdSeC60 Composite Films and Capture of Photogenerated Electrons with nC60 Cluster Shell. J. Am. Chem. Soc., 2008, 130, 8890–8891. 5. Kongkanand, A.; Kamat, P. V., Electron Storage in Single Wall Carbon Nanotubes. Fermi Level Equilibration in Semiconductor–SWCNT Suspensions. ACS Nano, 2007, 1, 13-21. 6. Williams, G.; Seger, B.; Kamat, P. V., TiO2-Graphene Nanocomposites. UV-Assisted Photocatalytic Reduction of Graphene Oxide. ACS Nano, 2008, 2, 1487-1491.
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Sunday March 28, 2010; 15:45
The Rise of Graphene: Catalysis and Nanocomposite Applications M. Samy El-Shall Department of Chemistry, Virginia Commonwealth University Richmond, Virginia 23284, USA E-mail:
[email protected] Graphene has attracted great interest both for a fundamental understanding of its unique structural and electronic properties and for important potential applications in nanoelectronics and devices. The combination of highest mobility, thermal, chemical and mechanical stability with the high surface area offers many interesting applications in a wide range of fields including heterogeneous catalysis where metallic and bimetallic nanoparticle catalysts can be efficiently dispersed on the graphene sheets. We have developed a facile and scalable chemical reduction method assisted by microwave irradiation1 for the synthesis of chemically converted graphene sheets and metal nanoparticles dispersed on the graphene sheets.2 In this talk we will present another novel method for the synthesis of graphene from graphite oxide by a fast laser irradiation process that does not involve the use chemical reducing agents and allows the production of high quality graphene for many applications in electronics, devices and catalyst support. We will also present several examples of nanocatalysis involving metallic and bimetallic supported nanoparticle catalysts.2,3 However, the most interesting study involves the use of a palladium/graphene (Pd/G) nanocatalyst for the synthesis of complex organic molecules using the Suzuki, Heck and Sonogashira coupling reactions. These reactions have typically been performed under homogeneous conditions to enhance the catalytic activity and selectivity for specific reactions. However, the issues associated with homogeneous catalysis remain a challenge to the broader application of these synthetic tools due to the lack of recyclability and potential contamination from residual metal in the reaction product. Our results demonstrate, for the first time, that the Pd/G is a high active catalyst for the Suzuki, Heck and Sonogashira C-C coupling reactions. This highly catalytic activity is accompanied by an unusual recyclability of the catalyst, over seven times, with essentially no drop in activity and a reaction that achieves 100% yield. Reasons for the exceptional activity and stability of the Pd/G catalyst will be discussed. References 1. V. Abdelsayed, A. Aljarash, and M. S. El-Shall, Chem. Mater. 2009, 21, 2825-2834. 2. M. S. El-Shall, V. Abdelsayed, A. S. Khder, H. M. A. Hassan, H. M. El-Kaderi, and T. Reich, J. Mater. Chem. 2009, 19, 7625-7631. 3. H. M. A. Hassan, V. Abdelsayed, A. S. Khder, K. M. AbouZeid, J. Terner and M. S. ElShall, J. Mater. Chem., 2009, 19, 3832-3837.
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ABSTRACTS Second Day Monday, March 29, 2010 SESSION-3 FUNDAMENTALS OF NANOCATALYSIS-1 9:00 – 11:00 Lecture 1
Fundamentals of Surface Reactions & Mechanisms Francisco Zaera Lecture 2
Tutorial for Characterizing Catalysts using Probe Molecules Mark G. White
SESSION-4 FUNDAMENTALS OF NANOCATALYSIS-2 11:30 – 13:30
Lecture 1 Supported Metal Clusters: Spectroscopic and Microscopic Evidence of Synthesis, Structure, Reactivity, and Catalysis Bruce Gates Lecture 2 Nanostructured Surfaces for Sensing and Catalysis Applications Ahmed Galal
SESSION-5 FUNDAMENTALS OF NANOCATALYSIS-3 16:00 – 18:00
Lecture 1 Observation of Chemical Reactions on Surfaces using STM. Watching Individual Molecules do their Molecular Dances John T Yates, Jr. Lecture 2 Surface Enhanced Raman Spectroscopy as Nanoscience Hassan Talaat
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Monday March 29, 2010; 9:00
Fundamentals of Surface Reactions and Mechanisms Francisco Zaera Department of Chemistry University of California, Riverside, CA 92521, USA E-mail:
[email protected] Achieving high selectivities is arguably the main challenge in heterogeneous catalysis in the 21st century: more selective catalysis may not only be cheaper because it does not waste reactants or require expensive separation procedures, but also greener, avoiding the generation of polluting byproducts. Control of selectivity in heterogeneous catalysis has traditionally been hampered by both a lack of understanding of the molecular details that define such selectivity and the limited range of synthetic tools available to make catalysts with the specific properties required. However, progress in surface science as well as in nanotechnology and selfassembly synthesis is changing that. Here we report on studies from our laboratory using model systems to pinpoint the mechanistic factors that define selectivity in a number of increasingly subtle hydrocarbon hydrogenation and dehydrogenation reactions. The first examples show how the regioselectivity of hydrogen elimination from alkyl species adsorbed on metals is affected by the electronic properties of the surface: while nickel promotes the extraction of hydrogen atoms from the carbon directly bonded to the surface, a step that leads to undesirable cracking reactions, platinum allows for dehydrogenation further down the hydrocarbon chain and therefore facilitate more desirable isomerization processes. In a second set of examples, the issue of selectivity in alkene isomerizations involving either doublebond migrations or cis-trans interconversions is addressed. In those cases the key mechanistic steps require hydrogen abstraction from a ! carbon in the hydrocarbon chain (the second from the surface), and selectivity is defined by steric considerations around the different hydrogens available at those positions. A particular exciting observation from our work in this area is the unique ability that close-packed surfaces of platinum have in promoting the thermodynamically unfavorable but highly desirable conversion of trans alkenes to their cis counterparts; new shape-controlled catalysts were prepared to take advantage of that behavior. Finally, the more subtle issue of enantioselectivity is discussed. Chiral compounds can be produced via hydrogenation of so called prochiral reactants such as asymmetric ketones, but regular metal catalysts are achiral and therefore lead to the production of racemic mixtures. However, chirality can be bestowed on catalytic surfaces by the adsorption of chiral modifiers. Individual molecules of these modifiers may be able, by themselves, to provide the required chiral environment on the surface for such enantioselectivity, as is the case with cinchona alkaloids, but simpler molecules may also assemble into chiral supramolecular structures held together by the surface; in both cases, a specific surface chiral site is produced with the help of molecular adsorbates. The examples to be discussed in this presentation not only highlight the need to design and prepare heterogeneous catalysts with sophisticated surface sites in order to promote reactions selectively, but also hint at some of the tools available to accomplish that task.
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Monday March 29, 2010; 10:00
Tutorial for Characterizing Catalysts using Probe Molecules Mark G. White Dave C. Swalm School of Chemical Engineering Mississippi State University, Mississippi State, MS 39762-9595 E-mail:
[email protected] I. Description of heterogeneous catalysts II. Characterizing total surface area of materials a. Non-porous b. Porous i. Pores characterized by two-dimension (cylindrical pores) ii. Pores characterized by thee-dimensions (slit-shaped pores) iii. Plug-gauge total adsorption experiments in zeolites III. Characterizing the active surface area of supported metal catalysts a. Supported Pt i. H2 titration ii. CO titration b. Supported Cu i. N2O titration ii. H2/O2 redox iii. H2S poisoning experiments IV. Characterizing the active surface area of supported metal oxide catalysts a. Acid catalysts i. Lewis acidity 1. Perylene titration 2. Pyridine IR 3. NO titration of Cu(II) oxide ii. Brønsted acidity 1. Pyridine IR 2. Hexamethyldisilazane reaction with surface protons iii. Titrating strength of acid sites 1. 13C-NMR-MAS of labeled acetone to determine acid strengths. 2. Temperature programmed desorption of a base molecule 3. Microcalorimetry -TGA of a base molecule desorption b. Base catalysts i. Titration with carbon dioxide--hydrotalcite ii. Titration with benzoic acid—titania iii. Titration with sulfur dioxide—supported MgO/alumina c. Zeolite catalysts i. Titrating the internal, reactive surface area and total reactive surface areas with reactive probe molecules of differing sizes.
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ii. Hoffmann elimination reaction in zeolites to determine the framework SiO2/Al2O3 ratio. Monday March 29, 2010; 11:30
Supported Metal Clusters: Spectroscopic and Microscopic Evidence of Synthesis, Structure, Reactivity, and Catalysis Bruce C. Gates Department of Chemical Engineering and Materials Science University of California at Davis, CA 95616 USA E-mail:
[email protected] Metal clusters on supports are an important class of industrial catalyst, but understanding of their structures is hindered by the smallness and nonuniformity of the clusters and by the heterogeneity of the supports and the nonuniformity of the metal–support interactions. In attempts to gain fundamental understanding of this class of catalyst, we have strived to prepare uniform and well-defined metal clusters on supports that are themselves uniform or facilitate the structural characterization. The supported metal clusters were prepared from organometallic precursors (e.g., Ir(C2H4)2(acac), Rh(C2H4)2(acac), Ru3(CO)12, and Os3(CO)12), imaged with atomic resolution by use of aberration-corrected STEM, and characterized with methods including extended X-ray absorption fine structure (EXAFS), X-ray absorption near edge structure (XANES), and infrared (IR) spectroscopies. The quantitative structural characterizations provide the strongest evidence available demonstrating how EXAFS and TEM agree and reinforce each other in the determination of cluster sizes (Fig. 1). Transient spectra demonstrate the steps in bimetallic cluster formation on MgO from Ru3(CO)12 and Os3(CO)12 in the presence of H2 (Fig. 2) and provide more fundamental information about cluster synthesis than has been obtained for solution reactions, which are complicated by solvent effects. The reversible formation and breakup of tetrairidium clusters on a zeolite support was followed in real time with EXAFS, XANES, and IR spectroscopies, and the data show how it is possible to tune the structures of catalytically active species by choice of the reactive atmosphere. Results such as these place the chemistry of supported metal clusters on an essentially molecular foundation and provide links to the chemistry of supported metals more generally.
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Figure 1. Cluster sizes determined by EXAFS spectroscopy and TEM.
First Steps of Bimetallic Cluster Formation
1. Decarbonylation and aggregation of Ru clusters 2. Decarbonylation of Os clusters 3. Bimetallic cluster formation Figure. 2. Schematic representation of steps in bimetallic cluster formation from Ru3(CO)12 and Os3(CO)12 on MgO in the presence of H2.
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Monday March 29, 2010; 12:30
Nano-Structured Surfaces for Sensing and Catalysis Applications Nada F. Atta, Soher A. Darwish, Shimaa M. Ali, Maher F. El-Kady, Ali M. Abdel Mageed, Hatem M. Amin, Rasha A. Ahmed, Ikram Hamdy, Eman F. Mohamed, Yasser M. Abdel Rahman, Ahmed Abdel Fatah, Ahmed Galal* Department of Chemistry, Faculty of Science University of Cairo, Postal Code 12613, Giza-Egypt Email:
[email protected] Most of chemical transformations take place at the interface between two phases. The chemical and physical structure of the surface of a solid substrate can be tailor designed for specific and selective reactions. Several applications benefits from this approach, for instance electrochemical sensor is an example for the determination of biological and organic molecules. Molecular recognition that is the specific interaction between two or more entities, generally molecules through non-covalent interactions such as hydrogen bonding, hydrophobic forces, van der Waals forces, electro-static interactions, coordination or pi-pi-interactions is another example. In some cases, the interaction is defined as host-guest where molecular recognition exhibit molecular complementary resulting structures. Some models for the applications of polymer surfaces modified with nano-structured metals for the determination of neurotransmitters will be presented. The smallest molecule could be considered as diatomic hydrogen with a length close to 150 picometer (that is equivalent to 1.50 Å). Small organic molecules, on the other hand, used as precursors for synthetic reactions have dimensions ranging from few Å to some 100 Å. Industrial catalysis generally takes place at the nanoscale (or subnanoscale). Most of the catalysts are made of metal particles of a few nanometers in size and in particular all the elementary reaction steps occur at the atomic (or molecular) scale. Thus, catalysis seems to be intrinsically a nanoscale phenomenon. Therefore, the word nanocatalysis, should not apply to the catalytic phenomenon itself but to the intrinsic properties of the catalysts, that may change in the nanoscale. The most important property which influences catalysis is the electronic structure. The evolution of binding energy of valence electrons affects the change in catalytic properties. In fact, it depends on the exact number of atoms in the cluster. When the clusters, however, reach a size of about 30–50 atoms, the electronic structure evolves smoothly towards the bulk limit. We will present our recent findings for a new class of perovskites that is synthesized using microwave technique. The prepared perovskites were used in the catalytic production of hydrogen gas. Other, surfaces were also prepared from nano-deposited metal particles for selective determination of neurotransmitters. Several advantages were realized using the newly prepared surfaces; these include high efficiency in production of hydrogen and high selectivity of given chemical species in complex matrices.
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References 1- Electrodeposited metals at conducting polymer electrodes. I- Effect of particle size
2-
3-
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6-
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and film thickness on electrochemical response, Nada F. Atta, A. Galal, F. Khalifa, Appl. Surf. Sci., 253, 4273–4282, (2007). Electrodeposited metals at conducting polymer electrodes. II- Study of the oxidation of methanol at poly(3-methylthiophene) modified with Pt-Pd co-catalyst, Ahmed Galal, Nada F. Atta, Soher A. Darwish, Shimaa M. Ali, Topics in Catalysis, 47, 7383, (2008). Palladium nanoclusters-coated poly(furan) as a novel sensor for catecholamine neurotransmitters and paracetamol, Nada F. Atta, Maher F. El-Kady, A. Galal, Sens. Actuators, B, 141, 566-574, (2009). Smart electrochemical sensor for some neurotransmitters using imprinted sol–gel films, Nada F. Atta, Ali M. Abdel-Mageed, Talanta, 80, 511-518, (2009). Electrocatalytic evolution of hydrogen on a novel SrPdO3 perovskite electrode, A. Galal, Nada F. Atta, Soher A. Darwish, Ahmed Abdel Fatah, Shimaa M. Ali, J. Power Sources, 195, 3806-3809, (2010). Synthesis, structure and catalytic activity of nano-structured Sr-Ru-O type perovskite for hydrogen production, A. Galal, Shimaa M. Ali, Soher A. Darwish, Ahmed A. Abd El Fatah, Nada F. Atta, in press, Appl. Catal.A:General, doi:10.1016/j.apcata.2010.02.015 (2010). Determination of catecholamines and other compounds using pd nanoclusters poly (N-methylpyrrole) electrode in pharmaceuticals and biological fluids, Nada F. Atta, Maher F. El-Kady and Ahmed Galal, in press, Anal. Biochem., doi:10.1016/j.ab.2010.01.001, (2010)
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Monday March 29, 2010; 16:00
Observation of Chemical Reactions on Surfaces using STMWatching Individual Molecules do their Molecular Dances John T. Yates, Jr. Department of Chemistry University of Virginia, Charlottesville, VA 22904 E-mail:
[email protected] The scanning tunneling microscope (STM) has revolutionized the investigation of surface chemistry. In this talk I will show how the microscope was developed historically and some recent applications to the study of chemical reactivity on the Au(111) surface. The microscope has been used to study the adsorption of the simplest alkane thiol- CH3SH, observing the breaking of the S-H bond in this molecule, yielding a CH3S species. Remarkably, a Au adatom from the interior of the solid Au is involved in the surface bonding to produce CH3-S-Au-CH3 surface species. Also the disulfide, CH3SSCH3 can be used to make surface thiolate layers by scission of the S-S bond, and it will be shown how a free radical chain reaction occurs amongst self-assembled disulfide molecules on Au(111) and Au(001) surfaces. These observations of a chain reaction provide the first molecular details of this well-known reaction type since its discovery in the gas phase in the 1920's.
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Monday March 29, 2010; 17:00
Surface Enhanced Raman Spectroscopy as Nanoscience Hassan Talaat Faculty of Science, Ain Shams University, Cairo, Egypt E-mail:
[email protected] The discovery of surface enhanced Raman scattering (SERS) more than 30 years ago, of adsorbed molecules on rough Ag electrodes[1], has opened a new field that can be truly scribed as the first nanoscience [2]. In SERS the Raman spectra of molecules on specially prepared metal surfaces (nanoparticles) is observed to have intensity that exceeds by 5 to 14 orders of magnitude[3,4] what is excepted in the absence of these nanoparticles. Since the inception of SERS, the origin of such enhancement has been reasoned to electromagnetic ( EM )effect and to chemical ( charge transfer ) effect. The first, has been demonstrated to give the major part (up to 11 orders of magnitude ) of the enhancement , and is the result of highly concentrated EM fields associated with strong localized surface plasmon resonances (LSPR) at interstitial sites of the metal nanostructure surfaces with closely spaced features. The second effect generally results in a 2 or 3 order of magnitude [2] enhancement is not discussed in this presentation. Theoretical and computational studies have shown that LSPR enhancement depends critically on the size and specific geometry of the nanostructured metal particles as well as the separation between these particles. . In this work, gold nanoparticles of different shapes (spheres, nanorods, etched prisms, and sharp prisms)have been prepared using the seed mediated growth method to act as substrates for Raman measurements. Also array of regularly oriented gold nanoprisms were prepared using the nanosphere lithography (NSL), as well as electron beam lithography (EBL), have been used to study the effect of the interparticle distance on SERS. Our results demonstrate that the sharp prisms give the highest SERS enhancements, and that the variation of the enhancement is exponentially decreasing with increasing the interstitial distance between the nanoprisms. References [1] Fleischman,M.P.;Hendra,J.;McQuillan,A.Chem.Phys.Lett. 1974,26,163 66; Jeanmaire,D.L.;Van ,Duyne ,R.P.J. Electroanal.Chem.1977,84,120; Albrecht,M.G.;Creighton,J.A.J.Am.Chem. Soc.1977,99, 5215-5217. [2] Moskovits,M.J.RamanSpectrosc.2005,36,485. [3] Nie,S.;Emory,S.R.Science1997,275,1102-1106. [4] Kneipp,K.;Wang,Y.;Kneipp,H.;Itzkan,I.;Dasari,R.R.;Feld, M.S.Phys.Rev.Lett.1996,76,2444-2447.
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ABSTRACTS Third Day Tuesday, March 30, 2010
SESSION-6
SUPPORTED METAL OXIDES 9:00 – 11:00 Lecture 1 Synthesis and Characterization of Highly-Dispersed, Supported Metal Oxide Catalysts Mark G. White Lecture 2 Selective Oxidation of Methanol to Formaldehyde over Molybdenum Oxide Supported on Nano-Hydroxyapatite Catalysts Abd El-Aziz Mohamed Said
SESSION-7
NATURAL GAS & WATER-GAS SHIFT 11:30 – 13:30 Lecture 1 Oxidative Coupling of Natural Gas using Nano-Membrane Technology Magdy M. Nasrallah Lecture 2 Recent Developments in the Application of Nanoparticles of Differently Prepared Modified Metal Gold / Supported Catalysts for the Water Gas Shift Activity Rabee Gabr
SESSION-8
PETROCHEMICAL CATALYSIS 16:00 – 18:00 Lecture 1 Petrochemicals Processing: Past Experience and Future Prospects Mohammed Elsokkary Lecture 2 A View on Catalysis in the Process Development Department in EPRI Kadri Abu El-Gheit
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Tuesday March 30, 2010; 9:00
Synthesis and Characterization of Highly-Dispersed, Supported Metal Oxide Catalysts Mark G. White Dave C. Swalm School of Chemical Engineering Mississippi State University, Mississippi State, MS 39762-9595 E-mail:
[email protected] I. Description of the approach using polynuclear metal complexes as catalyst precursors a. Mechanisms for attaching metal complexes to oxide surfaces b. Influence of support surface chemistry upon the attachment mechanisms II. Types of metal complexes used a. Cationic metal complexes b. Neutral metal complexes III. Modeling the attachment of metal complexes to oxide supports a. Semi-empirical MO methods to predict equilibrium geometries b. Semi-empirical MO methods to predict IR of supported metal complexes IV. Characterizing the supported metal complexes a. Powder XRD b. FTIR of supported metal complexes, effect of loading c. Thermal decomposition of supported metal complexes d. Gravimetric adsorption of probe molecules e. Magnetic methods to characterize selected metal complexes on supports f. UV-Vis methods to characterize selected metal complexes on supports g. Characterization of supported metal complexes by EXAFS V. Use of decomposed metal complexes on support as adsorbents and catalysts a. Copper-based systems b. Vanadium-based systems c. Titanium-based systems d. Gold-based systems e. Mixed metal oxides as weak acids f. Supported MgO as a selective adsorbent for SO2
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Tuesday March 30, 2010; 10:00
Selective Oxidation of Methanol to Formaldehyde Over Molybdenum Oxide Supported on Nano-Hydroxyapatite Catalysts Abd EL-Aziz A Said*, Mohamed M M Abd El-Wahab and Alian M. Alian Chemistry Department, Faculty of Science Assiut, University, Assiut, Egypt E-mail:
[email protected] Nano-hydroxyapatite -supported different ratios of molybdenum oxide (1 to 50 % w/w) were prepared by the impregnation method and calcinated at 400, 500, 600 and 700 oC in a static air atmosphere. The catalysts were characterized by thermogravimetry (TG), differential thermogravimetry (DTA), FT-IR spectroscopy, X-ray diffraction (XRD), and nitrogen sorption measurements. The surface acidity and basicity of the catalyst was investigated by the dehydration-dehydrogenation of isopropanol pyridine and 2,6-dimethyl pyridine. The gas–phase oxidation of methanol to formaldehyde was carried out in a conventional fixed flow bed reactor. The obtained results clearly showed that hydroxyapatite–MoO3 systems were active and selective towards the formation of formaldehyde.
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Tuesday March 30, 2010; 11:30
Oxidative Coupling of Natural Gas using Nano-Membrane Technology Magdy M. Nasrallah Department of Petroleum and Energy Engineering The American University in Cairo, Cairo, Egypt Email:
[email protected] & Jasmine Abdel Raouf Department of Chemical Engineering, Cairo University, Giza, Egypt Natural gas, containing primarily (>95%) methane, is a resource that rivals liquid petroleum in abundance. With inevitable depletion of liquid petroleum and a concomitant increase in natural gas reserves, it is expected that methane will eventually become a major resource for chemicals and liquid fuels. Both direct and indirect routes have been studied for Methane convertion. The indirect route relies on production of synthesis gas (H2 and CO mixture) by steam reforming or partial oxidative reaction of methane, followed by conversion of the synthesis gas to higher hydrocarbons by Fischer Tropsch process. The representative method in the direct route is oxidative coupling of methane (OCM) to ethane and ethylene, a feedstock for synthesis of liquid fuels or a large number of synthetic materials. In OCM, CH4 and O2 react over a catalyst, mostly oxides, at elevated temperatures to form C2 products (ethane and ethylene). However, the reaction often leads to the formation of the thermodynamically more favored CO2. It is generally agreed that OCM on an oxide catalyst follows a unique heterogeneous-homogeneous reaction mechanism: methyl radicals are generated on the solid surface and coupled to form C2 in the gas phase. The CO2 is formed by oxidizing carbon containing species mostly in the gas phase, and possibly also on the catalyst surface. The inherent problem is that oxygen required for OCM can react with CH4 and C2 products to form CO2 and a higher selectivity is always compromised with a lower C2 yield on all catalysts to about 25% which is lower than the economically attractive C2 yield threshold (30%). Nanotechnology has been proposed for membrane development with the objective of optimizing charge transport and enhancing OCM for optimum transformation to higher hydrocarbons and liquefaction. Among numerous perovskite–type oxides studied, La1-xSrxCo1-yFeyO3-d (LSCF) series, have attracted increasing attentions. The principal investigator published numerous papers related to the LSCF-type perovskite applications. This work exploits nano membrane materials of the LSCF type oxides with particle size ranging from 15 to 20 nm. These features resulted in the attractive improvement of performance. Nano scale structures have received significant attention, the properties can change by the size because of quantum effect when the size is reduced to nanometer level. The decrease of the size is also expected to enhance the catalytic activity, due to the resulting increase of the total surface area and active sites with unsaturated bonding. A parametric study is carried out in an attempt to investigate the effect of the nano structure on the defect concentration,
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oxygen vacancies, and the flux of oxygen through the membrane. Also, its affect on the kinetics, the rate, the selectivity, and the yield of the OCM reactions will be addressed.
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Tuesday March 30, 2010; 12:30
Recent Developments in the Application of the Nanoparticles of Differently Prepared Modified Metal Gold /Supported Catalysts for the Water Gas Shift Activity Rabei M. Gabr Chemistry Department, Assiut University, Assiut, Egypt E-mail:
[email protected],
[email protected] The Water gas Shift (WGS) reaction (H2O+CO!H2+CO) is an important step in a number of chemical processes for the production of H2.Athough the WGS technology is well established and widely used in large scale steady-state operation, such as hydrogen or ammonia plants, the interest for the WGS reaction has been growing significantly in the last years, as a result of the important advance in fuel cell technology. In addition, the (WGS) reaction is a historic reaction system. It plays a pivotal role in various industrial fields such as steam reforming of methanol, ammonia synthesis and conversion of syngas into a variety of important chemicals. Moreover; the promotion of WGS activity are of the main roles played by different metal/support catalyst in the automobile three-way catalysts, due to its ability to enlarge fast reduction/oxidation cycles. The main actor in a catalytic process is the catalyst which often consists of small metal particles dispersed on an inert support. The metal particles are the key components of the catalyst. The activity of the catalyst will generally depend on the size of metal particles, where a catalyst with small particles will give high activity due to the large number of atoms available on the metal particles surfaces. The water gas shift (WGS) activity of different metals/support catalysts has been studied. Two different techniques were used for the preparation of the catalystdeposition-precipitation and modified version of deposition- precipitation. The affect of different synthesis procedures on the WGS activity has been followed using HRTEM combined with EDS, X-ray diffraction and FT-IR In order to examine the molecules involved in the forward as well as the reverse WGS reactions. The elucidation of reaction mechanism is a challenge to develop highly active and stable low-temperature shift catalysts.
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Tuesday March 30, 2010; 16:00
Petrochemicals Processing: Past Experience and Future Prospects M. Elsokkary Petrochemicals Division, Egyptian Petroleum Research Institute (EPRI) Cairo, Egypt E-mail:
[email protected] The presentation deals with historical background of the petrochemical industry and its present situation. The petrochemicals Feedstock and Products will be discussed. Petrochemical Processes including Basic Processes, such as Steam Cracking and reforming are illustrated. Production Costs, (Capital costs, Operating Costs) and Added Value are other objectives for the presentation. Growth in Petrochemicals Past Experience; Future Prospects will be present with details. Illustrative Petrochemical Technology Roadmap (2000-2025) is presented in different stages. Stage1: Renewal, Stage2: Alternate feed stocks and Stage3: New chemistries. Egypt's Petrochemical Master Plan (2002-2022) Objectives and outlines will be elaborated.
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Tuesday March 30, 2010; 17:00
A View on Catalysis in the Process Development Department in EPRI Ahmed Kadry Aboul-Gheit Catalysis Division, Egyptian Petroleum Research Institute (EPRI) Cairo, Egypt E-mail:
[email protected] Nominally, a catalyst is any substance which participates in a chemical reaction and causes its rate acceleration, but which can (in principle) be recovered in its original form after the reaction, to be reused. Catalysts are traditionally classified into two categories: homogeneous and heterogeneous, depending on whether or not they are soluble. However, practical catalysts are solid, e.g, metals, metal oxides (supported or unsupported), etc. Heterogeneous catalysis cannot yet be described as a truly predictive science. Hence, more fundamental knowledge about the intrinsic nature of active sites is critical to the rational development of better catalysts. There is first a need to define and then control the atomic structure of the active sites, which involves the preparation of materials with well-defined architectures on length scales somewhat longer than the molecular. In addition, a materials science revolution is in progress and methods for the preparation and characterization of macroscopic materials and prediction of their properties have now been realized. Recently, we started work on the preparation and characterization of thin film nanocatalysts in the form of coatings on glass sheets to be used as catalysts for the photodegradation of chlorophenols, or polyaromatic hydrocarbons in water. Three papers were published; one in 2008 and two in 2009. I supervised 3 thesis in this field (2006-2008). Furthermore, we prepared a nano-platinum supported on Zeolites to be used as catalysts for the hydroisomerization of n-paraffins in petroleum light naphtha to produce high octane gasoline. Also, we published two papers (2008, 2009) on natural gas direct conversion to petrochemicals using metal oxides on zeolite support.
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Tuesday March 30, 2010; 20:00
After Dinner Talk Ethics of Scientific Publication: How to Write an Effective Scientific Paper Prashant V. Kamat Department of Chemistry and Biochemistry, Department of Chemical and Biomolecular Engineering, and Radiation Laboratory, University of Notre Dame, Notre Dame, IN 46556 E-mail:
[email protected] Sharing scientific knowledge through publications is an integral part of research career. Since more and more organizations evaluate scientific productivity by scholarly publication rates, the concern regarding research ethics becomes an important issue. The lecture will address following questions. What are common practices of publishing scientific work? What is scientific misconduct? What are common misconceptions? How to make your next paper an effective publication? Please download a copy of the paper “On Being a Scientist” –available free (One copy of for each person) from U.S. National Academy Press. http://www.nap.edu/catalog/12192.html
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ABSTRACTS Forth Day Wednesday, March 31, 2010
SESSION-9 NANOMATERIALS FOR ENERGY & ENVIRONMENT-1 9:00 – 11:00 Lecture 1 Carbon Nanostructures for Energy Conversion Prashant V. Kamat Lecture 2 Effect of Preparation Parameters on the Properties of TiO2 Nanoparticles for Dye Sensitized Solar Cells Abd El-Hady Besheir Kashyout
SESSION-10 NANOMATERIALS FOR ENERGY & ENVIRONMENT-2 11:30 – 13:30 Lecture 1 Nanomaterials in Environmental Processes Vicki Grassian Lecture 2 Fundamental Aspects of Photochemistry on TiO2 Surfaces-Using Sunlight for Environmental Remediation John T Yates, Jr.
SESSION-11 NANOMATERIALS FOR ENERGY APPLICATIONS 16:00 – 18:00 Lecture 1 Plasmonic-Semiconductor Hybrid Nanostructures for Photo-Electronic Device Fabrication Mona Bakr Mohamed Lecture 2 Design and In-situ Measurements of Catalytic Conversion and Electrochemical-EnergyStorage Materials: A Bright Future for Synchrotron-based Energy Science Faisal M. Alamgir
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Wednesday March 31, 2010; 9:00
Carbon Nanostructures for Energy Conversion Prashant V. Kamat Department of Chemistry and Biochemistry, Department of Chemical and Biomolecular Engineering, and Radiation Laboratory, University of Notre Dame, Notre Dame, IN 46556 E-mail:
[email protected] Carbon nanostructures (single wall carbon nanotubes and graphene) are well suited as scaffolds to collect electrons from excited semiconductor nanocrystals (CdSe quantum dots) and transport them to the conducting electrode surface. 1-D architectures provide the directionality for electron transport and reduce charge recombination pathways at the grain boundaries (Scheme 1). The charge separation between excited CdSe semiconductor quantum dots and stacked-cup carbon nanotubes (SCCNT) has been successfully tapped to generate photocurrent in a quantum dot sensitized solar cell (QDSC). The ability of carbon nanotubes and grahene oxide to collect and transport electrons from excited semiconductor anoparticles has been established from photocurrent and spectroscopy measurements. Composites of semiconductor nanoparticles carbon nanostructures have the potential to develop effective light energy harvesting strategies. Scheme 1.
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Wednesday March 31, 2010; 10:00
Effect of Preparation Parameters on the Properties of TiO2 Nanoparticles for Dye Sensitized Solar Cells A. B. Kashyout*, M. Soliman1 and M. Fathy Advanced Technology and New Materials Research Institute Mubarak City for Scientific Research and Technology Applications (MuCSAT) New Borg El-Arab City, P.O. Box 21934, Alexandria, Egypt E-mail:
[email protected] 1
Institute of Graduate Studies and Research, Alexandria University 163 Horrya Avenue, P.O. Box 832, Shatby, 21526 Alexandria, Egypt Nano-sized TiO2 powders have been prepared by sol-gel method. Influence of the different preparation parameters on the TiO2 nano-powder properties was investigated. Thermal gravemetric analysis (TGA) was used to examine the thermal properties of the produced TiO2 nanoparticles. Yield efficiency of the resulted nanoparticles was calculated and the reaction effciencey was estimated. Maximun effciency of 98.9% was achieved at autoclaving temperature of 245 ºC for time duration of 12 hrs. X-ray diffraction analyses show the presence of anatase structure at low and high autoclaving temperatures. Fraction of rutile phase appeared with increasing the calcination temperature and reach 40% at 850 ºC. High resolution transmission electron micsoscopy (HRTEM) showed spherical nanoparticles of 8-9 nm at autoclaving temperature of 130 ºC, while elongated nanoparticles of 14-18 nm in length and 9 nm in width were observed at autoclaving temperature of 245 ºC. The solar cell performance was measured for various TiO2 dye sensitized solar cells. The sample of high autoclaving temperature gave an improvement in efficiency to be 8.5 % while those of lower autoclaving temperature had an effieiency of 7.29 %. An enhancement in both open circuit voltage (Voc) and fill factor (FF) is obviously detected, where elongated nanoparticles are measured by HRTEM, which could improve the electrnonic conductivity and consequently FF and Voc.
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Wednesday March 31, 2010; 11:30
Nanomaterials in Environmental Processes Vicki H. Grassian Departments of Chemistry & Chemical and Biochemical Engineering University of Iowa, Iowa City, IA 52242-1294 E-mail:
[email protected] Both natural and engineered oxide nanomaterials play important roles in environmental processes. In the case of engineered nanomaterials, e.g. nanocyrstalline zeolites which have high external and internal surface areas, the properties can be tailored for a number of different environmental applications including deNOx catalysis and carbon dioxide removal and conversion. For naturally occurring oxide nanomaterials, e.g. iron oxides, the size dependent properties and surface chemistry will impact biogeochemical cycles. In this talk, some specific examples of the size-dependent properties and surface chemistry of both natural and engineered oxide nanomaterials in environmental processes will be discussed.
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Wednesday March 31, 2010; 12:30
Fundamental Aspects of Photochemistry on TiO2 Surfaces- Using Sunlight for Environmental Remediation John T. Yates, Jr. Department of Chemistry University of Virginia, Charlottesville, VA 22904 E-mail:
[email protected] Titanium dioxide is widely used for the solar-driven photooxidation of environmental contaminants. This occurs by the excitation of electron-hole pairs in the TiO2 and by redox processes that then occur on the surfaces the charge carriers move to the surface. We have used the measurement of simple photochemical processes on a TiO2(110) single crystal surface to monitor the kinetics of electron-hole pair recombination inside the solid. In addition, defective Ti3+ interstitial ions in the TiO2 bulk have been monitored as they diffuse through the solid to the surface to react with adsorbed oxygen, and the kinetics of this diffusion process to grow TiOx layers on top of the surface has been studied. Such TiOx layers are important in controlling the activity of metal catalysts supported by TiO2.
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Wednesday March 31, 2010; 16:00
Plasmonic-Semicondcutor Hybrid Nanostructures for PhotoElectronic Device Fabrications Mona B. Mohamed National Institute of Laser Enhanced Science (NILES) Cairo University, Giza, Egypt E-mail:
[email protected] Localized surface plasmons have been shown to provide substantial efficiency enhancement in photoelectric effects with a range of semiconducting materials and devices due to the scattering from metal nanoparticles near their localized plasmon resonance. This would enhance the light absorption and the photocurrent obtained in any PV and LED configuration. This talk will summarize the collective optical and electrical properties of Core-shell metal-semiconductor hybrid nanostructure and how these properties depend on the size, shape of the metallic core and semiconductor shell thickness. Different methods to fabricate metal-semiconductor hybrid structures will be discussed in details. This talk will also highlight the possibility of using these nanocomposites to fabricate quantum dot solar cell devices, LED and Lasers.
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Wednesday March 31, 2010; 17:00
Design and In-situ Measurements of Catalytic Conversion and Electrochemical-Energy-Storage Materials: A Bright Future for Synchrotron-based Energy Science Faisal M. Alamgir Materials Science and Engineering Georgia Institute of Technology, Atlanta, GA 30332-0245 E-mail:
[email protected] Two fundamental concerns in the development of novel materials are, first, the design of structure with atomic-scale precision in order to affect functionality, and second, the direct, realtime, measurement of that designed structure under operating conditions. Only a concerted effort along both of these fronts can reveal the fundamental aspects of the role of design on functionality. This is particularly true for the new generation of materials for energy harnessing and conversion where the size, shape and internal compositional architecture of functional materials are being manipulated in order to produce breakthroughs in energy science. On the design front, robust core-shell architectures are predicted to have significant effects in the catalysis, (electro/photo)catalysis, Li-battery electrochemistry and photovoltaics. We will look at the layer by layer growth of compositional architectures and discuss the effects of “core-shell” architectures on catalytic activity on the future of energy science. On the real-time measurement front we will look at the latest developments on synchrotron-based techniques. Due to the tunability of synchrotron X-rays speciesspecific information can be obtained using X-ray Absorption Spectroscopy (XAS) from nearly every known constituent element of energy-related materials. Using XAS, the chemical state and the local atomic structure from a material can be obtained from a single experiment. In addition, the high brightness, high coherence and short pulse trains allow synchrotron light to be used for species-specific, in-situ studies at high temporal and energy resolutions. We will look at examples of in-situ (and ex-situ) XAS measurements in the area of energy storage (Li-ion battery intercalation reactions), energy conversion (surface reactions on fuel-cell catalysts) and energy harvesting (catalytic H2 production from ethanol).
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ABSTRACTS Fifth Day Thursday, April 1, 2010 SESSION-12 GOLD-BASED NANOCATALYSTS 9:00 – 11:00 Lecture 1 Confining Resonant Photons to the Nano-Gold Length Scale: The New Properties and Applications in Material Science, Nanobiology and Cancer Nano-Medicine Mostafa El-Sayed Lecture 2 Catalysis by Nanosized Gold: The Nature of the Active Site D. Wayne Goodman
SESSION-13 IR CATALYSIS STUDIES 11:30 – 13:30 Lecture 1 Infrared Studies of Interest to Catalysis and Microelectronics Francisco Zaera Lecture 2 IR Observation of Adsorptive and Catalytic Interactions on Metal and Metal Oxide Surfaces Mohammed Ibrahim Zaki
SESSION-14 PLASMONIC & HYBRID NANOSTRUCTURED MATERILAS 16:00 – 18:00 Lecture 1 Laser Vaporization Controlled Condensation for the Synthesis of Supported Nanoparticle Catalysts, Nanoalloys & Up-Converting Nanoparticles M. Samy El-Shall Lecture 2 An Integrated Approach using Spectroscopy, Microscopy and Particle Sizing Methods to Investigate Chemistry on the Nanoscale Vicki Grassian
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Thursday April 1, 2010; 9:00
Confining Resonant Photons to the Nano-Gold Length Scale: The New Properties and Applications in Material Science, Nanobiology and Cancer Nano-Medicine Mostafa A. El-Sayed Laser Dynamics Laboratory, Georgia Institute of Technology Atlanta, GA 30332-0245, USA E-mail:
[email protected] New fields such as optoelectronics, sensors, nanocatalysis, nanomotors and nanomedicine use the new exciting properties1-3 of gold and silver nanoparticles. Some of the most exciting properties arise when resonant photons are captured by these nanoparticles of the right size and shape. This excites the localized surface plasmon oscillation resulting from the coherent excitation of the free electrons in the conduction band. This greatly enhances the electromagnetic fields of the captured photon on the surface of the nanoparticle which strongly enhances their Radiative properties as well as that of any electronic system that falls within the range of this field. The effect of the coupling between close nanoparticles change their color (used as nano-ruler)4, increase or decrease the Raman scattering intensity of adsorbed molecules5, enhance the nonradiative properties of near electronic systems like the relaxation of hot electrons in semiconductors6, the rate of exciton annihilation in conducting polymers7 or the rate of retinal photo-isomerization and proton pump in Bacterio-Rhodopsin photosynthesis8. The strong Radiative properties of gold nanoparticles are used in imaging and the sensitive detection of cancer cells in vitro9 and in-vivo11. The strongly absorbed photon energy is rapidly converted into heat. This localized heating of the gold nanoparticles can heat and destroy attached cancer (or sick) cells and is thus used in Vitro and in-Vivo cancer therapy10,11. Very recently, non-photo-thermal techniques of using gold nano-particles in Cancer Therapy have been developed.12 References 1. Burda, C.; Chen, X.; Narayanan, R.; El-Sayed, M.A., “The Chemistry and Properties of Nanocrystals of Different Shapes”, Chem. Rev. 105 (4), 1025-1102, (2005) (Invited Review Article). 2. Huang, X.l Neretina, S.; El-Sayed, M.A., Gold Nanorods: From Synthesis and Properties to Biological and Biomedical Applications. Advanced Materials, 21(48),4880–4910 (2009). (Invited review article) 3. Stephan Link, Mostafa A. El-Sayed, “Optical Properties and Ultrafast Dynamics of Metallic Nanocrystals”, Annual Review Phys. Chem., 54:331-66, (2003) Invited. 4. Prashant K. Jain, W.Huang, and M.A. El-Sayed, "On the universal scaling” Nano Letters, 7, 2080, (2007). 5. Mahmoud, M. A., El-Sayed, M.A., Aggregation of gold Nanoframes reduces, rather than enhances SERS efficiency due to the tradeoff of the inter- and intra particle plasmonic fields. Nano Letters, 9(8), 3025-3031(2009).
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6. Svetlana Neretina, Wei Qian, Erik C. Dreaden, Robert A. Hughes, John S., Peter Mascher, Mostafa A. El-Sayed, "Plasmon Field Effects on the Nonradiative Relaxation of Hot Electrons in an Electronically Quantized System: CdTe-Au Core-Shell Nanowires," Nano Letters 8(8), 2410-2418 (2008) 7. Mahmoud, M. A, and Adam Poncheri, J. Am. Chem Soc., In press. 8. Arianna Biesso, Wei Qian, Mostafa A. El-Sayed, "Gold nanoparticle plasmonic effect on the retinal photoisomerisation and the proton pump in the photocycle of the other photosynthetic system in nature, bacteriorhodopsin," Journal of the American Chemical Society, 130(11), 3258-+, (2008); 131,2442, 2009 9. El-Sayed, Ivan; Huang, Xiaohua; El-Sayed, Mostafa A., “Surface Plasmon Resonance Scattering and Absorption of anti-EGFR Antibody Conjugated Gold Nanoparticles in Cancer Diagnostics; Applications in Oral Cancer,” Nano Letters 4(5), 829-834, (2005). (ISI hot paper) 10. Xiaohua Huang; Ivan H. El-Sayed; Wei Qian and Mostafa A. El-Sayed, “Cancer Cell Imaging and Photothermal Therapy in Near-Infrared Region by Using Gold Nanorods,” Journal of American Chem Soc., 128, 2115-2120, (2006). (the most cited paper in the field of chemistry, ISI, Oct-Dec 2007). 11. Erin B. Dickerson , Erik C. Dreaden , Xiaohua Huang , Ivan H. El-Sayed et al, Goldnanorod assisted nearinfrared plasmonic photothermal therapy of squamous cell carcinoma in mice” , Cancer Letters 269, 57-66 (2008). 12. Bin Kang, Meg Mackay and M. A. El-Sayed, J. Am. Chem. Soc, 2010, 132 (5), pp 1517– 1519.
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Thursday April 1, 2010; 10:00
Catalysis by Nanosized Au: The Nature of the Active Site D. W. Goodman Department of Chemistry, Texas A&M University College Station, TX 77842-3012, USA E-mail:
[email protected] The special electronic, structural, and chemical properties of gold clusters supported on single crystalline titania surfaces have been detailed and contrasted with the corresponding properties of bulk gold. The gold clusters investigated vary in size from a few atoms to many. An array of surface techniques including reaction kinetics of carbon monoxide oxidation has been used to correlate catalytic function of these surfaces with their physical and electronic properties. Of special interest are the special physical and chemical properties that develop with metal cluster size reduction and/or metal-support interaction.
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Thursday April 1, 2010; 11:30
Infrared Studies of Surfaces of Interest to Catalysis and Microelectronics Francisco Zaera Department of Chemistry University of California, Riverside, CA 92521, USA E-mail:
[email protected] Examples from our laboratory on applications of infrared spectroscopy to the characterization of surfaces of relevance to catalysis and microelectronics fabrication will be presented. Transmission IR absorption spectroscopy has been used to identify key intermediates on high-surface area solids relevant to catalysis as well as in film deposition processes, and also to characterize the oxidation state of supported metals via chemical titrations. Attenuated total reflection (ATR) setups have been used to investigate the anchoring of porphyrins on solid substrates for applications in the development of molecular memories, and also to establish the reaction mechanism of atomic layer deposition (ALD) processes. Reflection- Absorption IR spectroscopy (RAIRS) is employed to characterize key adsorbates, to determine adsorption geometries, and to titrate surface chemical sites. The RAIRS approach is often used to look at well-characterized single-crystal surfaces under ultrahigh vacuum conditions, but additional setups have been developed to also be able to interrogate gas-solid and liquid-solid interfaces in-situ. Our ability to investigate the liquid-solid interface has been particularly useful to probe the chiral modification of catalytic systems.
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Thursday April 1, 2010; 12:30
IR Observation of Adsorptive and Catalytic Interactions on Metal and Metal Oxide Surfaces Mohamed I. Zaki Chemistry Department, Faculty of Science, Minia University, El-Minia 61519, Egypt E-mail:
[email protected] Catalysis is in large measure brought about by chemical perturbation of a reactant or reactants through interaction with the catalyst surface. At gas/solid interfaces the gas molecules colloid with the solid surface mostly inelastically. If the loss in energy is significant, the molecules may stick to the surface. On the surface the molecules may get physically adsorbed (weakly bound) and, thus, can still be able to wander about, or may become restricted to certain sites by chemical adsorption (strongly bound) and, consequently, get energetically perturbed and activated for a chemical change. The chemical change may be confined to a molecular dissociation into smaller species, or may be brought about by the involvement in a surface catalytic reaction of unimolecular or bimolecular kinetics. The talk should help presenting techniques and potential of in-situ Fourier-transform infrared spectroscopy in observing adsorptive and catalytic events at molecular level. Results obtained for interactions established at the interfaces of a number of reactive and irreactive probe molecules (including CO, pyridine, 2-propanol and methybutynol) with supported and unsupported metal (e.g., Rh and Ni) and metal oxide (MoOx, AlOx, CrOx, CeOx, ZrOx ..etc) catalysts will be used to reveal nature of adsorbed species, as well as various characteristics of adsorption sites (e.g., acidbase properties, coordination and oxidation states, and dispersion). Moreover, mathematical apparatus adopted in refining and analyzing the spectral data will be brought into prominence.
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Thursday April 1, 2010; 16:00
Laser Vaporization Controlled Condensation for the Synthesis of Supported Catalysts, Nanoalloys & Up-Converting Nanoparticles M. Samy El-Shall Department of Chemistry, Virginia Commonwealth University Richmond, Virginia 23284, USA E-mail:
[email protected] In this lecture, I will review the vapor phase synthesis of nanoparticles with a focus on the LVCC method.1-3 This method uniquely combines the features of pulsed laser vaporization with the controlled condensation process from the vapor phase under well-defined conditions of temperature and pressure. It allows the synthesis of nanoalloys with controlled compositions as well as the incorporation of dopant ions within the lattice of the desired nanocrystals. The LVCC method produces highly crystalline nanoparticles and therefore, eliminates the long post-annealing process typically required by other synthesis methods. Furthermore, the method does not involve the use of any chemical precursors or solvents and therefore, it provides a simple and yet effective synthetic route for contamination-free, highly crystalline, and controlled doping of nanoparticles. The coupling of the LVCC technique with a differential mobility analyzer (DMA) allows the synthesis of size-selected semiconductor, metal and intermetallic nanoparticles from the vapor phase. Finally, the application of an electric field during the LVCC process leads to the assembly of nanoparticles into filaments and fibers. Enormous electrostatic interaction due to dipole forces is observed between nanoparticles to form chain filaments and between the chains to form tree-like assemblies. Three examples of the synthesis of nanoparticles by the LVCC method will be discussed. First, is the synthesis of intermetallic (FeAl, NiAl, TiAl) and alloy (Au-Ag, Au-Pd, Au-Pt) nanoparticles. The formation of nanoalloys is concluded from the observation of one plasmon absorption band at a wavelength that varies with the composition of the nanoalloy. Also, the XRD data and HRTEM-EDX data can be used to confirm the formation of nanoparticle alloys and not simply mixtures of the individual nanoparticles.1 In the second example, the synthesis of nanoparticle catalysts (for CO oxidation) characterized by large surface area, high dispersion and strong metal-support interaction will be presented. The use of the bimetallic nanoparticles as catalysts provides an opportunity for tuning the catalytic activity to the desired performance depending on the composition of the nanoalloy, the nature of the oxide support, and the size and shape of the nanoparticle alloys.2 Finally, the application of the LVCC method for the synthesis of up-converting (UC) phosphors nanoparticles will be presented. These particles covert near-infrared (NIR) photons to higher energy visible or UV light via multiple absorptions or energy transfer. The incorporation of several dopants such as Yb3+, Er3+, Ho3+, and Tm3+ with controlled concentrations within the lattice of host nanocrystals such as Y2O3 will be
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discussed.3 UC nanoparticles are used to convert NIR photons into red, green, blue and white light for a variety of applications that include display devices, back light sources, sensors, biolabeling and photodynamic therapy. References 1. Laser Synthesis of Bimetallic Nanoalloys in the Vapor and Liquid Phases and the Magnetic Properties of PdM and PtM Nanoparticles (M = Fe, Co and Ni) V. Abdelsayed, G. Glaspell, M. Nguyen, J. Howe and M. S. El-Shall, Faraday Discussion 2008, 138, 163-180. 2. Nanocatalysis on Supported Oxides for CO Oxidation G. Glaspell, H. M. A. Hassan, A. Elzatahry, V. Abdelsayed and M. S. El-Shall, Topics in Catalysis, 2008, 47, 22-31. 3. Vapor Phase Synthesis of Upconverting Y2O3 Nanocrystals Doped with Yb3+, Er3+, Ho3+ and Tm3+ to Generate Red, Green, Blue and White Light G. Glaspell, J. Anderson, J. Wilkins and M. S. El-Shall, J. Phys. Chem. C. 2008, 112, 1152711531.
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Thursday April 1, 2010; 17:00
An Integrated Approach Using Spectroscopy, Microscopy and Particle Sizing Methods to Investigate Chemistry on the Nanoscale Vicki H. Grassian Departments of Chemistry & Chemical and Biochemical Engineering University of Iowa, Iowa City, IA 52242-1294 E-mail:
[email protected] In the studies discussed here, an integrated approach which utilizes methods from surface science, surface chemistry, solid state chemistry, colloid science and aerosol science, to investigate the chemical activity and physicochemial properties of metal and metal oxide particles on the nanoscale will be discussed. The approach combines state-of-the-art characterization of the bulk and surface properties of nanoparticles by using spectroscopy, microscopy and particle sizing instruments along with studies of the physicochemical properties of nanoparticles to better understand size-dependent processes of nanoparticles. Examples to be discussed include surface adsorption, surface chemistry, nanoparticle dissolution and nanoparticle aggregation of nanoscale titanium dioxide, iron oxyhydroxide, copper and silver nanoparticles.
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ABSTRACTS Seventh Day Saturday , April 3, 2010 SESSION-15 DESIGN & SYNTHESIS OF NANOMATERIALS FOR ENERGY APPLICATIONS 9:00 – 11:00 Lecture 1 Design of Nanomaterials for Energy Applications Puru Jena Lecture 2 Synthesis, Characterization and Evaluation of New Materials for Hydrogen Storage Nahla Isamil
SESSION-16 HIGH SURFACE AREA MATERIALS 11:30 – 13:15 Lecture 1 Metal-Organic Materials:Strategies toward Functional Porous Materials Mohamed Eddaoudi Lecture 2 Acid Catalyzed Organic Transformations by Heteropoly Tungstophosphoric Acid Supported on MCM-41 and MIL-101 Abd Elrahman Khedr
SESSION-17 ATMOSPHERIC & ENVIRONMENTAL CATALYSIS 15:30 – 18:00 Lecture 1 Atmospheric Processes on Aerosol and Cloud Surface
Joseph S. Francisco Lecture 2 Nanocatalysts for CO Oxidation on Different Supports: Mesopourous MCM-41, MIL-101 & Mixed Metal Oxides Hassan M. Ahmed Hassan Lecture 3 New Nano-Crystalline Electrode Materials for Green Hydrogen Fuel Production from Seawater Electrolysis Ahmed Abd El-Menniem
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Saturday April 3, 2010; 9:00
Design of Nanomaterials for Energy Applications Puru Jena Department of Physics Virginia Commonwealth University, Richmond, VA E-mail:
[email protected] Nanomaterials, due to their reduced size and dimension, possess unusual properties not seen in their bulk form. This has opened the door to the design and synthesis of novel materials with tailored properties. My presentation will involve three components. First I will describe state-of-the-art theoretical techniques that are used to study the structure property relationships of nanomaterials with particular emphasis on energetic materials. Examples will include nanomaterials for hydrogen storage and for high energy density applications. For the hydrogen economy to succeed, materials capable of storing hydrogen with gravimetric density of about 10 wt% is needed. To meet this target, host materials have to consist of elements lighter than Aluminum. Unfortunately, the bonding of hydrogen in these materials is either too strong or too weak and ways must be found to tune the hydrogen bond strength so that these materials can be used for mobile applications. I will discuss how the novel properties of materials at the nanoscale can improve the thermodynamics and kinetics of hydrogen. In particular, I will discuss how carbon based nanostructures such as nanotubes and fullerenes can not only be used as catalysts to improve hydrogen uptake and release in complex light metal hydrides such as alanates, borohydrides, and imides but also how they can be functionalized with metal atoms atoms to adsorb hydrogen in a novel quasi-molecular form. I will also discuss the role of electric fields in hydrogen storage. These results, based upon density functional theory and quantum molecular dynamics, provide a fundamental understanding of the interaction of molecular hydrogen with hosts consisting of light elements. It is hoped that the understanding gained here can be useful in designing better materials for hydrogen storage. Results will be compared with available experimental data. The second application involves the design of molecular species where inner core electrons can participate in bonding and hence can bind to a larger number of halogen and oxygen atoms than traditionally known. In particular I will concentrate on a class of molecules called superhalogens. These are multi-atom chemical species with electron affinities that are much larger than those of the halogen atoms and typically consist of a central atom and several peripheral halogen or oxygen atoms. Because of their high electron affinities, superhalogens almost always exist as negative ions, usually as the anionic portions of salts. While numerous superhalogen anions, such as permanganates (MnO4-) and perchlorates (ClO4-) are known, many more are waiting to be discovered. I will describe a new class of superhalogens consisting of coinage metal atoms (Cu, Ag, and Au) interacting with fluorine. Not only these atoms can bind up to seven F atoms, far exceeding the values expected from their nominal valence, but also the electron affinity of these superhalogen molecules can be as high
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as 8 eV, more than a factor two larger than that of Cl, the element with the highest electron affinity in the periodic table. These superhalogens have the potential to serve as building blocks of new high energy-density materials capable of combating biological agents.
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Saturday April 3, 2010; 10:15
Synthesis, Characterization and Evaluation of New Materials for Hydrogen Storage Nahla Ismail National Research Centre, Cairo, Egypt E-mail:
[email protected]
Research on new materials to be tested to store hydrogen is of great interest. Microporous and layered materials and polymeric materials are synthesized and its hydrogen adsorption properties are examined. Titanosilicates of different types ETS4, natisite and sitinakite are synthesized hydrothermally at 200C. Natisite and sitinakite has been also synthesized from natural Egyptian silica of high purity. The use of natural silica has increased the porosity of the natisite and sitinakite which by its turn has enhanced the hydrogen storage capacity. Lay ered transition metal phosphorous trisulphides are synthesized by solid state reaction in evacuated silica ampoules. The hydrogen capacity adsorbed in interlayer gap reached 2.2 wt% up to 20 bar and at 77 K. Different hyperbranched polymer systems beside a nanocomposite are employed as hydrogen storing materials. The polymers used are aliphatic hyperbranched poly urea, polyamide amine (PAMAM) and polyamide amine/ vanandium pentoxide (PAMAM/ V2O5) nanocomposite. Hydrogen adsorption isotherms showed linear relationship with increasing pressure. The materials showed hydrogen storing ability up to 2.2 wt%. New results for the hydrogen storage capacity of graphene and Metal-Organic Frameworks (MOFs) will be presented. Graphene has been prepared by the reduction of graphite oxide prepared by the Hammer method. The graphene sheets produced are able to adsorb 0.28 wt.% hydrogen at 273 K and 20 bar. At 77 K and the same applied pressure (20 bar), the sample adsorbs 3.4 wt.% hydrogen. On the other hand, MIL-101 sample displays hydrogen storage capacity of 4.4wt.% at 77K and 20 bar.
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Saturday April 3, 2010; 11:30
Metal-Organic Materials: Strategies toward Functional Porous Materials Mohamed Eddaoudi Department of Chemistry, The University of South Florida 4202 E. Fowler Avenue, CHE205, Tampa, Florida, 33620, USA E-mail:
[email protected] The quest for functional materials targeted for specific applications is ever increasing as societal needs and demands mount with advancing technology. One class of inorganic-organic hybrid materials, metal-organic materials (MOMs), has burgeoned in recent years due, in part, to effective design strategies (i.e. reticular chemistry) for their synthesis and their inherent [and readily interchangeable] hybrid, highly functional character. The molecular building block (MBB) approach introduces the ability to generate rigid and directional building blocks, mostly in situ, for the construction of MOMs having specific underlying networks and/or targeted functions/properties. Here we will discuss three basic strategies based on the MBB approach. Three classes of MBBs can be targeted and utilized in the assembly of functional MOMs: 1) single-metal-ion-based MBBs, which promote the rational construction, by forcing rigidity and directionality through control of the metal coordination sphere and judicious selection of suitable hetero-functional (N-, Ocoordination) organic ligands, of porous MOMs with extra-large cavities, including zeolite-like metal-organic frameworks (ZMOFs);1 2) multi-nuclear metal clusterbased MBBs, where, for example, simple metal-carboxylate clusters possess multiple metal-oxygen coordination bonds that result in the generation of rigid nodes with fixed geometry that, when combined with organic ligands of specific geometry, lead to the construction of desired MOMs (e.g. soc-MOFs);2 and 3) supermolecular building blocks (SBBs), which involve enhanced built-in directional and structural information (e.g. high degree of symmetry and connectivity) compared to simple MBBs and allow the construction of high-connectivity nets (e.g. rht-MOFs).3 The MBB approach and associated strategies, as well as physical properties of some corresponding MOMs (i.e. porosity, hydrogen sorption, catalysis, inclusion and sensing) will be discussed. !
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References [1]. (a) Liu, Y.; Kravtsov, V. Ch.; Larsen, R. W.; Eddaoudi M. Chem. Commun. 1488-1490, 2006; (b) Liu, Y.; Kravtsov, V. Ch.; Eddaoudi, M. Angew. Chem. Int. Ed. 47, 8446-8449, 2008; (c) Alkordi, M. H.; Liu, Y.; Larsen, R. W.; Eubank, J. F.; Eddaoudi, M. J. Am. Chem. Soc. 130, 12639-12641, 2008. [2]. Liu, Y.; Eubank, J. F.; Cairns, A. J.; Eckert, J.; Kravtsov, V. Ch.; Luebke, R.; Eddaoudi, M. Angew. Chem. Int. Ed. 46, 3278-3283, 2007. [3] Nouar, F.; Eubank, J. F.; Bousquet, T.; Wojtas, L.; Zaworotko, M. J.; Eddaoudi, M. J. Am. Chem. Soc., 130, 1833-1835, 2008.
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Saturday April 3, 2010; 12:30
Acid Catalyzed Organic Transformations by Heteropoly Tungstophosphoric Acid Supported on MCM-41 Abd El Rahman S. Khder Department of Chemistry, Faculty of Science El-Mansoura University, El-Mansoure, Egypt E-mail:
[email protected] Solid acid catalysts of the catalytically active Keggin-type 12-tungstophosphoric acid (H3PW12O40, HPW) incorporated within MCM-41 and the highly porous metalorganic framework MIL-101 is prepared through a simple and effective impregnation method. Characterization of the catalysts using X-ray diffraction, TEM, FT-IR and Raman spectroscopy, TGA, surface area and porosity measurements and acid-base titration demonstrates the control of the catalyst properties by the percent loading of HPW within MCM-41 or MIL-101 support. The results show that the surface saturation coverage of MCM-41 is reached by 60 wt. % HPW. In the case of MIL-101, no evidence for aggregation of the HPW nanocrystals on the surface of MIL crystals is found with HPW loading up to 70 wt%. N2 sorption-desorption measurements reveal that samples with HPW loading up to 70 wt% retain their mesoporosity, thus allowing the HPW accessibility through the MIL substrate. The catalytic activities of these catalysts in promoting Pechmann reaction, esterification reaction and Friedel-Crafts acylation of anisole have been investigated. The results show that, both of the surface acidity and the catalytic activity sharply increase with the incorporation of HPW within the MCM-41 or the MIL-101 supports. For the HPW/MCM-41 and HPW/MIL-101 catalysts, the highest acidity and catalytic activity are obtained with 60wt % and 70 wt% HPW loading, respectively. The unique attributes of the high surface areas of MCM-41 and MIL-101 and the high dispersion of the HPW nanocrystals prohibit the conglomeration and deactivation of HPW, which leads to the enhancement of the catalytic properties. The HPW-MCM and HPW/MIL catalysts are potentially promising heterogeneous catalysts for acidcatalyzed organic transformations in environmentally friendly processes, to supersede the use of conventional homogeneous HPW catalysts.
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Saturday April 3, 2010; 15:30
Atmospheric Processes on Aerosol and Cloud Surfaces Joseph S. Francisco Department of Chemistry and Department of Earth and Atmospheric Sciences Purdue University, West Lafayette, Indiana 47907-2084 Email:
[email protected] How gas-phase materials become incorporated with cloud droplets has been an intriguing subject for decades, and considerable work has been done to understand the interactions between closed-shell molecules and liquid water. The interactions between open-shell radical species and liquid-phase cloud droplets, however, are not well understood. To probe these interactions we used quantum chemistry calculations to predict the energetics of the hydroperoxy radical (HO2) in the presence of a model cloud droplet surface. Our calculations show that it is energetically favorable for the radical to bind to the outside of the cage. This configuration and orientation of the radical binding will be discussed as well as the implication for chemistry. Free-energy calculations and molecular dynamics simulations provide some intriguing insight into the partitioning between radicals that are surface-bound and radicals that dissolve into the bulk. This may have important ramifications for our understanding of radical chemistry and may lend insight into the role that clouds and aerosols play in atmospheric chemical processes.
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Saturday April 3, 2010; 16:30
Nanocatalysts for CO Oxidation on Different Supports: Mesoporous MCM-41, MIL-101 & Mixed Metal Oxides Hassan M. A. Hassan Chemistry Department, Faculty of Science Suez Canal University, Suez, Egypt E-mail:
[email protected] The catalytic activity of supported nanocatalysts depends on the shape of the support and the extent of interaction with the catalyst. Several examples of supported nanocatalysts for the low temperature oxidation of CO will be discussed. In the first example, the synthesis of transition metal (TM) catalysts supported on MCM-41 will be presented. The surface area measurements reveal that MCM-41 has a total surface area of 982m2/g with an average pore radius size of 35Å. These results are confirmed by the XRD and TEM measurements. The catalytic activity of Pd/TM Oxide/MCM41 towards CO oxidation has been studied as a function of the Pd loading and the type of the transition metal oxide used. The Pd/Co3O4/MCM-41 catalyst shows the highest catalytic activity where 100% CO oxidation is achieved at 130oC with the 6 wt% Pd loading. In the second example, a facile, general and effective approach, based on microwave irradiation (MWI), has been developed for the incorporation of a variety of metallic and bimetallic nanoparticle catalysts within the highly porous coordination polymer MIL-101. Small Pd, Cu and Pd-Cu nanoparticles of 2-3 nm are incorporated within the pores and larger particles of 4-6 nm are supported on the surface of the MIL-101 crystals. The observed catalytic activities towards CO oxidation of the Pd nanocatalysts supported on the highly porous MIL-101 polymer are significantly higher than any other reported metal clusters supported on metal-organic frameworks. The Pd/MIL with 2.9 wt% Pd loading shows the highest catalytic activity with a full conversion of CO into CO2 achieved at 107 ºC. The observed high activity is attributed to the small metal nanoparticles imbedded within the pores of the MIL crystals. Finally, the MWI has been used for the synthesis of Au and Pd nanocatalysts supported on cerium-hafnium nanocrystalline solid solution (CexHf1-xO2, x = 0.6-0.8). The incorporation of Hf4+ ion into the CeO2 lattice enhances the redox ability of these supported catalysts. The catalyst 4%Au/0.8CeO2-0.2HfO2 shows the highest catalytic activity with a full conversion of CO into CO2 achieved at 73 ºC. This high activity is remarkable and implies that a variety of efficient catalysts can be designed and tested using this approach.
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Saturday April 3, 2010; 17:15
New Nano-Crystalline Electrode Materials for Green Hydrogen Fuel Production from Seawater Electrolysis Ahmed A. El-Moneim1,2,*, N.Diab2, E. El-Sherbiny2, K. Ebrahim2, N. A. El-Ghany2 1-Egyptian-Japanese University of Science and Technology, Borg El Arab, Alexandria, Egypt 2-National Research Centre, Giza, Egypt E-mail:
[email protected] For prevention of global warming and prevention of exhaustion of fossil fuels and uranium, renewable energy fuels should supplied to meet the demand of the whole world. We are proposing global carbon dioxide recycling as well as hydrogen fuel production, with the help of Tohoku Institute of technology, Sendai, Japan, for the use of renewable energy. Intermittent electricity generated by solar cell on deserts or wind turbine in on and/or offshore regions will converted to hydrogen by seawater electrolysis nearby sea or desert coasts, and hydrogen with no infrastructures of transportation will be used directly in internal combustion engine or converted to methane by reaction with carbon dioxide. Key materials necessary for this process are the anode and cathode for seawater electrolysis and the catalyst for conversion carbon dioxide into methane. We have been creating these key materials. For industrialization of green hydrogen technology based on seawater electrolysis, enormous evolution of toxic chlorine, which generally occurs on the anode, is not allowed. In addition, cheap cathode and anode with very low overpotentials during long term electrolysis are requested. Finally, optimum electrolyzer design with very low energetic loss is needed. The technical objective of the work in this presentation is to tailor anode and cathode materials meet selectivity, durability, reliability and cost effectiveness for environmentally and energetically efficient seawater electrolysis process. We succeed in tailoring the best ever know durable oxygen evolving anode, without formation of environmentally harmful chlorine, during electrolysis of acidic seawater. The best anode was continuously deposited from 0.2M Mn2+-0.003M Mo6+-xM N (N is either transition or rare earth metal cations) solutions of pH -0.1 at 600 A.m-2 for 1h on electroconductive IrO2/Ti substrate. It showed 100% and 97% oxygen evolution efficiency, with no loss in weight, after about 3000 and 6000h of electrolysis, respectively, at 1000A.m-2 We also succeed in developing durable electrodeposited NiMoC alloy electrodes for hydrogen evolution reaction on both expanded iron and nickel substrates. The NiMoC alloy electrodes show several order of magnitudes higher activity for HER than commercial carbon steel, expanded Ni and platinized electrodes. The durability (corrosion resistance) of NiMoC alloy electrodes is not significantly affected by the shutdown period of electrolysis process. Electrodes performance was explained in terms of structure, composition, conductivity and other physico-chemcial parameters.
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The overall system efficiency based on PEM technology was about 84% which is comparable to the value suggested by US Department of Energy (DOE) for producing hydrogen with reasonable price from forecourt sized electrolyzer.
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ABSTRACTS
Eighth Day Sunday , April 4, 2010
SESSION-18 CARBON NANOTUBES 9:00 – 10:45
Lecture 1 Metallic and Bimetallic Nanocatalysts for the Economic Synthesis of Decorated Carbon Nanotubes (CNT) for Environmental Applications Mahmoud H. Khedr Lecture 2 Heating and Cooling Dynamics of Carbon Nanotubes Observed by Temperature-Jump Spectroscopy and Electron Microscopy Omar F. Mohammed
SESSION-19 INTERNATIONAL COLLABORATION 13:00 – 15:00
Lecture 1 Funding Opportunities in International Collaborations for Materials Research and Education Zakya Kafafi Lecture 2 Overview of the American Chemical Society and U.S. efforts to celebrate the International Year of Chemistry 2011 Joseph S. Francisco
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Sunday April 4, 2010; 9:00
Metallic and Bimetallic Nanocatalysts for the Economic Synthesis of Decorated Carbon Nanotubes (CNTs) for Environmental Applications Mahmoud H. Khedr Nanomaterials Unit, Faculty of Science, Benisuef University Benisuef, Egypt E-mail:
[email protected] An overview of the synthesis methods and the properties of carbon nanotubes (CNTs) will be presented. Effective, simple and economically attractive methods for synthesis of CNTs and the modification of their surface structures will be presented. These modifications are expected to improve the catalytic, electrical, magnetic and mechanical properties of CNTs for a variety of important applications. One of these applications is the use of modified CNTs for the adsorption of heavy metals from sea water and river water to decrease the toxicity in fish farms. Other possible applications will be discussed.
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Sunday April 4, 2010; 10:00
Heating and Cooling Dynamics of Carbon Nanotubes Observed by Temperature- Jump Spectroscopy and Electron Microscopy Omar F. Mohammed*, Peter C. Samartzis and Ahmed H. Zewail Physical Biology Center for Ultrafast Science and Technology, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, CA 91125, USA E-mail:
[email protected] Although the thermal effects of suspended carbon nanotubes (CNTs) in organic and aqueous solutions have been extensively studied1-2, by studying bubble formation due to heat transfer from the hot nanotubes to the solvent and subsequent evaporation, the dynamics of the CNTs heating and how long the CNTs stay hot after electronic excitation (cooling rate to the surrounding medium) are still essentially opaque. Here, we report real time observation of the dynamics of CNTs following infrared (IR) ultrafast excitation. Two techniques are invoked. The first is the ultrafast T-jump probing, which provides the time scales involved in CNTs heating and cooling. For this approach, carboxyl-functionalized CNTs were utilized in order to map heat rise/decay by monitoring the spectral change with time. The high solubility of the functionalized CNTs is essential for the investigation reported here, as it enables studies in different polar solvents. The second approach is direct imaging in our ultrafast electron microscope3, with an in situ infrared irradiation. The images provide the evidence for the heat transfer from the CNTs to the environment and the spatial extent of the heat wave following the irradiation. In conclusion, microscopy imaging indicates that the in situ CNTs irradiation with relatively low dosages of infrared radiation results in significant heating of the tubes, which in turn can melt nanoparticles at temperatures above 1300 K4. The ultrafast Tjump experiments, on the other hand, have revealed, for the first time, that the time scales of CNTs heating and cooling are on the tens and hundreds of picoseconds, respectively. Given the reported transient behavior, these observations suggest novel ways for a T-jump methodology, unhindered by the requirement for excitation of water in the study of biological structures5. They also provide the rates information needed for optimization of photothermal therapy that invokes infrared irradiation to selectively heat and annihilate cancer cells6. References (1) Izard, N.; Billaud, P.; Riehl, D.; Anglaret, E. Opt. Lett. 2005, 30, 1509. (2) Vivien, L.; Lancon, P.; Riehl, D.; Hache, F.; Anglaret, E. Carbon 2002, 40, 1789. (3) Lobastov, V. A.; Srinivasan, R.; Zewail, A. H. Proc. Natl. Acad. Sci. U. S. A. 2005, 102, 7069. (4) Mohammed, O. F.; Samartzis, P. C; Zewail, A. H. J. Am. Chem. Soc. 2009, 131, 16010. (5) Mohammed, O. F.; Jas, G. S.; Lin, M. M.; Zewail, A. H. Angew. Chem. Int. Ed. 2009, 48, 5628. (6) Jain, P. K.; Huang, X. H.; El-Sayed, I. H.; El-Sayed, M. A. Acc. Chem. Res. 2008, 41, 1578.
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Sunday April 4, 2010; 13:00
Funding Opportunities in International Collaborations for Materials Research and Education Zakya Kafafi Director, Division of Materials Research (DMR) National Science Foundation (NSF) Arlington, VA 22230, USA E-mail:
[email protected] During the signing ceremony of the American Recovery and Reinvestment Act, President Obama said that "this investment will ignite our imagination once more, spurring new discoveries and breakthroughs that will make our economy stronger, our nation more secure and our planet safer for our children." With the beginning of this new golden era for science, the community of materials research and education is well positioned to take upon this challenge and, demonstrate to the world how its various and diversified activities will impact our quality of life. An overview of the Division of Materials Research (DMR) plans for funding in FY 2010 and beyond will be presented. Educational and outreach programs that emphasize how the innovations resulting from materials research could revolutionize scientific disciplines, and lead to radically new technologies, better quality of life and improved world economy will be discussed. As science knows no boundaries, DMR is committed to prepare the future workforce to be agile thinkers in this universal environment and, in forging collaborations and cooperation among scientists and engineers around the world. This is consistent with President Obama’s vision for science and technology. In his historic speech at Cairo University, President Obama said that the U.S. will "launch a new fund to support technological development in Muslim-majority countries, and to help transfer ideas to the marketplace so they can create more jobs. We'll open centers of scientific excellence in Africa, the Middle East and Southeast Asia, and appoint new science envoys to collaborate on programs that develop new sources of energy, create green jobs, digitize records, clean water, grow new crops.”
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Sunday April 4, 2010; 14:00
Overview of the American Chemical Society and U.S. efforts to celebrate the International Year of Chemistry 2011 Joseph S. Francisco President, American Chemical Society Department of Chemistry and Department of Earth and Atmospheric Sciences Purdue University, West Lafayette, Indiana 47907-2084 Email:
[email protected] The aims and mission of the Egyptian Chemical Society (ECS) are to create a scientific environment and strengthen links between chemists in the country and improve teaching and learning skills and professional practice in the field of chemistry. This is a mission that corresponds very closely to the vision and mission of the American Chemical Society (ACS). The ACS vision is “Improving people’s lives through the transforming power of chemistry,” and its mission is “To advance the broader chemistry enterprise and its practitioners for the benefit of Earth and its people.” As chemistry is a central science that cuts across all disciplines, the ACS and ECS share many potential avenues to explore collaboration. The observance of the International Year of Chemistry in 2011 presents challenges and opportunities for our shared discipline and the chemical enterprise. How might the ECS and ACS work together to serve chemistry practitioners—who increasingly need to function globally – and to best address global issues, will be discussed.
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Poster Session I And Poster Session I I
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Poster Session I Monday, March 29, 2010 8:00 PM – 10:00 PM 1
Nanoparticle Chemistry from the Particle Perspective: Insights from Aerosol Particle Sizing Measurements Sherrie R. Elzey Department of Chemical & Biochemical Engineering University of Iowa, Iowa City
2
Preparation and Characterization of Polyvinyl Alcohol-CdTe Nanocomposites Magdah Dawy and Asma Al-Turki National Research Center, Dokki, Cairo, Egypt
3
Shape Controlled Anisotropic Gold, and Gold/Zinc Oxide Core/Shell Nanocrystals via Microwave Synthesis Natalie Herring, Khaled M. AbouZeid, Mona B. Mohamed and M. Samy El-Shall* Department of Chemistry Virginia Commonwealth University Richmond, VA, 23284-2006
4
Synthesis, Characterization and Spectroscopic Studies of CdS/polyaniline Core/Shell Nanocomposite R. Seoudi, M. Kamalb, A.A. Shabaka, E.M. Abdelrazek,W. Eisaa National Research Center, Dokki, Cairo, Egypt
5
Rational Synthesis of Semiconductor Quantum Dots Christopher M. Evans and Todd D. Krauss Department of Chemistry University of Rochester, Rochester, NY
6
Photothermal and Photoacoustic Characterization of Optical and Thermal Properties of Nanomaterials S. Negm Department of Physics and Mathematics Faculty of Engineering, (Shoubra), Benha Univwersity Egypt
7
Electron transfer between colloidal ZnO nanoparticles Hayoun, Rebecca; Whitaker, Kelly M.; Gamelin, Daniel R.; Mayer, James M. Department of Chemistry University of Washington, Seattle, WA
8
Preparation and Characterization of Nano-Biocatalyst for Industrial Applications
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A.A. Elzatahry and M.S. Mohyeldin Institute of Advanced technology and New materials, Mubarak City for Scientific Research and technology applications, New Borg Alarab, Alexandria, Egypt.
9
Plasmon-Exciton Coupling in Vertically Aligned Core-Shell CdTe-Au Nanorod Arrays Erik C. Dreaden, Svetlana Neretina, Wei Qian, Robert A. Hughes, John S. Preston, Peter Mascher, and Mostafa A. El-Sayed Laser Dynamics Laboratory School of Chemistry and Biochemistry Georgia Institute of Technology, Atlanta, Georgia 30332-0400,
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Structure Characterization of Nanocrystalline Zn1-xMnxSe Thin Films Synthesized by Inert Gas Condensation I. K. El Zawawi, K. Sedeek, A. Adam, Manal A. Mahdy Solid State Physics Department National Research Center, 12622 Dokki, Cairo, Egypt
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11
Growth Kinetics of Nanoparticles: Investigating the Effect of Sacrificial Nanoparticles to Produce Size Focusing (Quantized Ostwald Ripening) Pinar Dagtepe and Viktor Chikan Department of Chemistry Kansas State University , Manhattan, Kansas
12
Phase and conductivity dynamics of strontium hexaferrite nanocrystals in a hydrogen gas flow A. A. Fargali, M. K. Zayed, M. H. Khedr* and A. F. Moustafa Chemistry Department, Faculty of Science, Beni-Sueif University, BeniSueif-62111, Egypt.
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Electrodic Behavior of Pt Nanoparticles Coupled With CdSe Quantum Dots In Confined Media Clifton Harris Department of Chemistry and Biochemistry University of Notre Dame, Notre Dame, IN
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Kinetics of acetylene decomposition over reduced strontium hexaferrites catalyst for the production of carbon nanotubes M.H. Khedr*, A.A. Farghali, M.K. Zayed and A.F. Moustafa Chemistry Department, Faculty of Science, Beni-Sueif University, BeniSueif-62111, Egypt.
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Plasmonic Field Enhancement of the Exciton-Exciton Annihilation Process in a Poly(paraphenyleneethynylene) Fluorescent Polymer by Ag Nanocubes Adam J. Poncheri, Mahmoud A. Mahmoud, Ronnie L. Phillips, and Mostafa A. El-Sayed Laser Dynamics Laboratory School of Chemistry and Biochemistry Georgia Institute of Technology, Atlanta, Georgia 30332-0400
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Formation of Copper Nanoparticles by Nanosecond Laser Ablation
W. A. Ghaly, H. T. Mohsen, Y. A. Badr and A. I. Helal Nuclear Research Center, Atomic Energy Authority National Institute for Laser Enhanced Sciences, Cairo University, Cairo, Egypt
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17
Influence of Water on Radical-Molecular Reactions at Surfaces: Perspective from a Study of Water Atmosphere Surface Reaction Models R. J. Buszek and J.S. Francisco Department of Chemistry and Department of Earth and Atmospheric Sciences Purdue University, West Lafayette, Indiana
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Synthesis and Characterization of pH-Sensitive PAMPS/PVP Nanogels in Aqueous Media Ayman M. Atta*, Rasha A. M. El-Ghazawy, Reem K. Farag and Shymaa M. Elsaeed Egyptian Petroleum Research Institute Nasr City 11727, Cairo, Egypt
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Synthesis and Evaluation of Some Hydrophobically Modified Polyacrylamide (HMPAM) Nanolatexes Using Polymerizable Surfactants for Enhanced Oil Recovery Applications E. A. Elsharaky, M. R. Noor El-din, R. A. Elghazawy, N. Kandile and A. M. Alsabagh
Egyptian Petroleum Research Institute Cairo, Egypt
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Characterization of electrophoretically deposited nanocrystalline hydroxyapatite on 316L stainless steel for biomedical applications A. M. Elbasiony, N.A. Abdel Ghany and Y. A. Elewady Advanced Materials and Nanotechnology Lab Centre of Excellence for Advanced Sciences National Research Centre, Dokki, Cairo, Egypt
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EPRI researching works in the field of natural gas processing Tamer Zaki Department of Catalysis, Petroleum Refining Division Egyptian Petroleum Research Institute Cairo, Egypt
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Nanoparticle Chemistry from the Particle Perspective: Insights from Aerosol Particle Sizing Measurements Sherrie R. Elzey Department of Chemical & Biochemical Engineering University of Iowa, Iowa City E-mail:
[email protected] The recent explosion in applications of nanomaterials requires proper methods for characterization and analysis to facilitate advancements in nanoscience and nanotechnology. Because nanoparticles exhibit unique, size-dependent behavior, particle size effects cannot be ignored and must be explicitly monitored so that a fundamental understanding of the underlying size-dependent processes on the nanoscale can be discerned. This work uses an electrospray coupled to a scanning mobility particle sizer (ES-SMPS) to study particle size distributions (PSDs) of metal and metal oxide nanoparticles under varying chemical environments. A nanoparticle aerosol is generated from suspensions in aqueous and/or acidic solutions, and PSDs are monitored to observe shifts in particle size. Results offer insights into size-dependent nanoparticle properties.
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Preparation and Characterization of Polyvinyl Alcohol-CdTe Nanocomposites Magdah Dawy and Asma Al-Turki National Research Center, Dokki, Cairo, Egypt E-mail:
[email protected] Nano-sized TiO2 powders have been prepared by sol-gel method. Influence of the different preparation parameters on the TiO2 nano-powder properties were investigated. Thermal gravimetric analysis (TGA) was used to examine the thermal properties of the produced TiO2 nanoparticles. Yield efficiency of the resulted nanoparticles was calculated and the reaction efficiency was estimated. Maximum efficiency of 98.9% was achieved at autoclaving temperature of 245 ºC for time duration of 12 hrs. X-ray diffraction analyses show the presence of anatase structure at low and high autoclaving temperatures. Fraction of rutile phase appeared with increasing the calcination temperature and reach 40% at 850 ºC. High resolution transmission electron microscopy (HRTEM) showed spherical nanoparticles of 8-9 nm at autoclaving temperature of 130 ºC, while elongated nanoparticles of 14-18 nm in length and 9 nm in width were observed at autoclaving temperature of 245 ºC. The solar cell performance was measured for various TiO2 dye sensitized solar cells. The sample of high autoclaving temperature gave an improvement in efficiency to be 8.5 % while those of lower autoclaving temperature had an efficiency of 7.29 %. An enhancement in both open circuit voltage (Voc) and fill factor (FF) is obviously detected, where elongated nanoparticles are measured by HRTEM, which could improve the electronic conductivity and consequently FF and Voc.
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Shape Controlled Anisotropic Gold, and Gold/Zinc Oxide Core/Shell Nanocrystals via Microwave Synthesis Natalie Herring, Khaled M. AbouZeid, Mona B. Mohamed and M. Samy El-Shall* Department of Chemistry Virginia Commonwealth University, Richmond, VA, 23284-2006 Great recent interest has been focused on the anisotropic Au nanocrystals because of their appealing optical properties. The most interesting feature of the anisotropic shaped gold nanoparticles is that they have multiple absorption bands due to Surface Plasmon Resonances (SPR) along their multiple axes. These unique optical properties of anisotropic gold nanocrystals enable one to tune the SPR to any wavelength specific to a particular application from the visible to the near IR spectral regions. Using these nanomaterials in biomedical imaging, cancer therapy and diagnosis, catalysis, sensors and photonic devices is becoming a practical reality. A facile and fast one-pot microwave irradiation method has been developed to prepare different shapes of Au, and Au/ZnO core/shell nanocrystals capped with a mixture of oleyl amine and oleic acid. The size, shape and morphology of the nanocrystals could be tailored by varying the ratio of oleylamine to oleic acid, the microwave time, and the concentration of the precursor ions. These effects are directly reflected in the surface plasmon resonance properties of the resulting nanocrystals in the visible and near-infrared regions. The Au/ZnO Core/Shell nanocrystals were fully characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and transmission electron microscopy (TEM). This method may lend itself to the synthesis of more complex core/shell composites.
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Synthesis, Characterization and Spectroscopic Studies of CdS/polyaniline Core/Shell Nanocomposite R. Seoudi, M. Kamalb, A.A. Shabaka, E.M. Abdelrazek,W. Eisaa National Research Center, Dokki, Cairo, Egypt In this work, CdS/polyaniline (PANI) nanocomposite was synthesized by a novel method. Transmission electron microscope (TEM) images showed that the CdS/PANI nanocomposite had a core/shell structure. The crystal structure was studied using X-ray diffraction (XRD) and the obtained results showed that CdS had cubic structure. Fourier transform infrared (FTIR) spectroscopic measurements confirmed the formation of PANI at the surface of CdS nanoparticle. The prepared samples were further characterized using UV–visible (UV–vis) and fluorescence spectroscopy
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Rational Synthesis of Semiconductor Quantum Dots Christopher M. Evans and Todd D. Krauss Department of Chemistry University of Rochester, Rochester, NY E-mail:
[email protected] Colloidal semiconductor nanocrystals represent an important class of nanostructures that serve as model systems for fundamental investigations of quantum confinement and that also have potential for significant breakthroughs to advance applications over a broad range of fields from optoelectronics to biology. Over the past two decades, significant advances have been made regarding the synthesis of high quality nanoparticles with a controllable size, shape and composition. However, these syntheses are notoriously dependent on ill-defined details of the starting materials, reaction yields are poor, and exact reproducibility is extremely difficult to achieve, primarily because the fundamental reaction mechanism responsible for the initial stages of nanocrystal growth is largely undetermined. We will present studies of the chemical reaction mechanism describing the general synthesis of metal chalcogenide semiconductor quantum dots using a combination of optical spectroscopy, electron microscopy, mass spectrometry and nuclear magnetic resonance spectroscopy. In particular, we have identified specific chemical reactants critical for mediating the synthesis of semiconductor nanoparticles. These highly reactive species are typically found as impurities in the starting reagents, but are completely responsible for driving the kinetics of the nanocrystal formation. These findings have allowed us to determine a reaction pathway general to all phosphine based chalcogenide nanocrystal syntheses. Further, we also propose a complete reaction mechanism that provides a complete picture of how simple organometallic molecules can be transformed into nanoscale semiconductors comprising thousands of atoms. We have utilized these findings to improve reaction yields for CdSe and PbSe nanocrystals by over an order of magnitude, while producing nanocrystals of exceptional quality with respect to control over size, size distribution, and fluorescence efficiency. These results should allow for future identification of cheaper, safer, and greener precursors for large-scale preparations of high-quality nanocrystals.
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Photothermal and Photoacoustic Characterization of Optical and Thermal Properties of Nanomaterials S. Negm Department of Physics and Mathematics, Faculty of Engineering, (Shoubra), Benha University Egypt Photothermal (PT)spectroscopy proves to be a powerful technique to study the optical, electronic and thermal properties of nanomaterials in nondestructive manner without particular sample preparations. The presentation gives the results for metallic (gold) nano dots and rods and semiconductor (CdSe ) nanodots and rods, as well as core/shell (Ag/CdSe)nanoparticles.. . The gold nanoparticles have been prepared using the seed mediated growth method. Photoacoustic (PA) measurements show the surface plasmon resonance (SPR) splitting into two modes (transverse and longitudinal) in case of gold nanorods and that the increase in the aspect ratio of the nanorods leads to red-shifts of the longitudinal SPR. CdSe QDs and QRods were fabricated by the chemical solution deposition (CD) technique.. The average diameters of the CdSe QDs and QRods are estimated from the PA spectra using the effective mass approximation model giving values that are comparable to those obtained by scanning tunneling microscope (STM). The exciton energy of the CdSe QRs were also determined using second derivative of the PA spectra leading to estimates of the dimensions very close to the direct measurement by Thus, PA spectroscopy is useful in obtaining the QDs sizes as grown and with no further preparation. In addition, PA measurements provide also the thermal diffusivity and thermal conductivity which show decrease by at least an order of magnitude than the bulk value.
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Electron transfer between colloidal ZnO nanoparticles Hayoun, Rebecca; Whitaker, Kelly M.; Gamelin, Daniel R.; Mayer, James M. Department of Chemistry University of Washington, Seattle, WA
[email protected] Many nanoscale materials catalyze and undergo various redox processes. Most of these processes, particularly in the areas of energy and petrochemicals, involve protons as well as electrons. It has been shown that the redox potential (band edge energy) for most semiconducting nanomaterials (e.g. TiO2) depends strongly on proton activity, suggesting that these materials undergo proton-coupled electron transfer (PCET) reactions. We are exploring the fundamentals of how protons moderate redox reactions at nanoparticle surfaces, which is a critical part of understanding their catalytic properties. We are advancing a small molecule–based approach as a way to provide new insights into the role of protons in nanoparticle redox reactions. Here, we will present studies of charge transfer reactions involving colloidal 3-7 nm dodecylamine-capped ZnO nanoparticles using EPR and electronic absorption spectroscopies. Stable charged colloidal nanoparticles with electrons in their conduction bands have been prepared photochemically. Mixing suspensions of small charged ZnO nanoparticles with suspensions of larger uncharged ZnO particles rapidly results in stoichiometric transfer of reducing equivalents. No reaction was observed in the opposite direction, when large charged particles were mixed with smaller uncharged particles. This reactivity is consistent with expectations from consideration of quantum confinement effects on the conduction band edge potentials of these nanocrystals. Optical monitoring of these reactions supports these conclusions, as does EPR monitoring using Mn2+ dopants as secondary EPR probes. Kinetic and mechanistic aspects of this chemistry will be discussed. These studies of charge transfer reactions in nanoparticles, with a small molecule–type approach, are providing new insights into reaction chemistry such as PCET at nanoscale materials.
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Preparation and Characterization of Nano-Biocatalyst for Industrial Applications A.A. Elzatahry and M.S. Mohyeldin Institute of Advanced technology and New materials, Mubarak City for Scientific Research and technology applications, New Borg Alarab, Alexandria, Egypt. Poly(AN-MMA) nano-copolymers beads were prepared using precipitation polymerization technique and used as supports for enzyme immobilization to act as a biocatalyst. Factors affecting the polymerization yield such as Co-monomer ratio, Polymerization Time, Polymerization Temperatures, Initiator Concentration and Solvent Compassion were studied. The co-polymerization process was proved through FT-IR, TGA and Nitrogen content analysis. !-Galactosidase enzyme was covalently immobilized onto the nanobeads using glutaraldehyde as activating agent. The immobilization process was optimized by examining immobilized time, cross-linking time, enzyme concentration, glutaraldehyde concentration, the initial pH values of glutaraldehyde and the enzyme solution. As a result, the immobilized enzyme presented a higher storage, pH and thermal stability than the soluble enzyme. Immobilized enzyme has reusability of over 10 batchwise uses. The easy accessibility of the substrate to immobilized enzyme, ease of its immobilization on the prepared nano beads, enhanced stability of the immobilized enzyme, and comparable lactose hydrolysis in milk whey described in this work, make it a suitable product for future applications at laboratory and industrial scale.
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Plasmon-Exciton Coupling in Vertically Aligned Core-Shell CdTe-Au Nanorod Arrays Erik C. Dreaden,† Svetlana Neretina,†," Wei Qian,† Robert A. Hughes,‡ John S. Preston,‡,§ Peter Mascher§, and Mostafa A. El-Sayed*,†. Laser Dynamics Laboratory, School of Chemistry and Biochemistry Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA
[email protected] †
Laser Dynamics Laboratory, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA. " Department of Mechanical Engineering, Temple University, 1947 N. 12th St., Philadelphia, PA 19122, USA. ‡ Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario, L8S 4M1, Canada. § Department of Engineering Physics, McMaster University, Hamilton, Ontario, L8S 4L7, Canada. Gold nanoparticles possess unique optical properties associated with the resonant oscillation of conduction electrons at their surfaces – surface plasmons. The highly intense local electric fields generated by resonant excitation of surface plasmons is well known to enhance radiative relaxation (fluorescence), molecular vibrations (SERS, SEIRA), and energy transfer processes (FRET, photoisomerization). Plasmonic field effects on non-radiative processes is however, less understood. Our fundamental understanding of plasmonic interactions with semiconductors and their tunability will provide opportunities for future applications in solar energy harvesting and electronic device architecture. The studies presented here demonstrate the effects of plasmonic coupling on the mechanisms of non-radiative relaxation in a compound semiconductor. Vertically aligned core-shell CdTe-Au nanorods arrays were fabricated and the kinetics of non-radiative excitonic relaxation were examined as a function of surface plasmon cross section, field direction, and polarization mode. We show i) that relaxation rates can be enhanced by resonant excitation of surface plasmon modes, ii) that orientational anisotropy of the surface plasmon field direction can be used to tune such rates, and iii) that the mechanisms of this relaxation can be can be varied as a function of the mode of the plasmon field’s polarization. The intense electromagnetic fields of plasmonic nanoparticles, resulting from the excitation of their localized surface plasmon oscillations, are known to enhance radiative processes. Their effect on the nonradiative electronic processes, however, is not as well-documented. Here, we report on the enhancement of the nonradiative electronic relaxation rates in CdTe nanowires upon the addition of a thin gold nanoshell, especially at excitation energies overlapping with those of the surface plasmon oscillations. Some possible mechanisms by which localized surface plasmon fields can enhance nonradiative relaxation processes of any quantized electronic excitations are proposed. We studied the anisotropy of the influence of plasmonic fields, arising from the optical excitation of a gold nanoshell plasmon absorption at 770 nm, on the lifetime of the bandgap state of the CdTe core in vertically aligned CdTe-Au core-shell nanorods. The previously observed decrease in the lifetime was studied as a function of the tilt angle between the long axis of the nanorod and the electric field polarization direction of the plasmon inducing exciting light. It is observed that the strongest enhancement to the exciton relaxation rate occurs when the two axes are parallel to one another. These results are discussed in terms of the coupling between the exciton transition moment of the CdTe rod and the electric field polarization direction of the gold nanoshell plasmon at 770 nm, which was determined from theoretical modeling based on the discrete dipole approximation. The dependence of the plasmon field enhancement of the nonradiative relaxation rate of the band gap electrons in vertically aligned CdTe-Au core-shell nanorods on the plasmonic gold nanoshell thickness is examined. Increasing the thickness of the gold nanoshell from 15 to 26 nm is found to change the decay curve from being nonexponential and anisotropic to one that is fully exponential and isotropic (i.e.,
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independent of the nanorod orientation with respect to the exciting light polarization direction). Analysis of the kinetics of the possible electronic relaxation enhancement mechanisms is carried out, and DDA simulated properties of the induced plasmonic field of the thin and thick gold nanoshells are determined. On the basis of the conclusions of these treatments and the experimental results, it is concluded that by increasing the nanoshell thickness the relaxation processes evolve from multiple enhancement mechanisms, dominated by highly anisotropic Auger processes, to mechanism(s) involving first-order excited electron ejection process(es). The former is shown to give rise to nonexponential anisotropic decays in the dipolar plasmon field of the thin nanoshell, while the latter exhibits an exponential isotropic decay in the unpolarized plasmonic field of the thick nanoshell.
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Structure Characterization of Nanocrystalline Zn1-xMnxSe Thin Films Synthesized by Inert Gas Condensation 1
I. K. El Zawawi1, K. Sedeek2, A. Adam2, Manal A. Mahdy1 Solid State Physics Department, National Research Center, 12622 Dokki, Cairo, Egypt 2 Physics Department, Faculty of science (Girls), El-Azhar University,Cairo, Egypt. E-mail:
[email protected]
Undoped and Mn doped ZnSe nanostructure thin films of thickness 20, 50, 80, 100 and 120nm have been successfully synthesized. The thin films were deposited from ingot polycrystalline powder by inert gas condensation (IGC) technique with constant Argon flow of 2x10-3 Torr at 300 K. The energy dispersive Xray analysis (EDX) for prepared Zn1-xMnxSe thin films were carried out and showed that Mn contents (x) are 0.0, 0.05, 0.16 and 0.25. The as-prepared thin films of different thickness were examined by transmission electron microscopy (TEM). The crystallinity and the particle size ranging from 4-7nm was determined from diffraction patterns and microgragh images respectively. The grazing incident in-plane Xray diffraction (GIIXD) patterns of 80nm thick for Zn1-xMnxSe thin films showed that all examined films exhibit nanocrystalline single phase zinc blende structure. The diffraction peaks shows a broadening attributed to the small particle size in comparison to XRD patterns of poly crystalline ingot powders.
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Growth Kinetics of Nanoparticles: Investigating the Effect of Sacrificial Nanoparticles to Produce Size Focusing (Quantized Ostwald Ripening) Pinar Dagtepe and Viktor Chikan Department of Chemistry Kansas State University , Manhattan, Kansas E-mail:
[email protected]. Manipulating the growth of semiconductor nanoparticles (NP) is important for both technology and fundamental science. This work aims to investigate the growth of colloidal semiconductor NPs in the bimodal growth regime, when multiple distinct-sized NPs are present in a growth solution. In systematic experiments, CdSe NPs with different sizes are synthesized and mixed together and reacted to assess the ripening process. Monte Carlo Simulation is carried out to compare theory and the experiment. A widelyaccepted explanation of the growth kinetics of the NPs in high temperature coordinating solvents is described by Talapin et. al.1 The model calculates the size-dependent growth rate of the NPs, which leads to a good prediction of the self focusing and the Ostwald ripening2,3 of NP ensembles. In this study, NP solutions consisting of 2000 large particles of 3.5±0.35 nm radius and 80000 particles of 1±0.1 nm radius are simulated. For comparison, repeated injection technique is also simulated. The bimodal distribution technique is a slower process, which could lead to better control over the NP synthesis. The monomer oversaturation stays relatively low over the reaction time. This is crucial if one wants to avoid producing new nuclei that is difficult to control. If we compare the rate of nucleation in case of repeated injection vs. bimodal size focusing, one finds considerably reduced rate of re-nucleation for bimodal size focusing. This is important to develop a general methodology that extends the time required to achieve size focusing during the growth of NPs. Slower growth will reduce the effect of inhomogeneous mixing and temperatures inherent in a scaled up production. In addition, during the repeated injection the high monomer concentrations result in re-nucleation during focusing of NPs; therefore, a method that yield better control over the synthesis is desirable. Experimentally, our group has also observed by in situ absorbance and fluorescence spectroscopy4,5 that CdSe nanoparticles exhibit spontaneous ‘bimodal’ growth over several hours.4 In this bimodal growth regime, nanoparticles with well defined and very different sizes coexist in the solution at lower temperatures. The average size and size distribution of the nanoparticles is primarily controlled not by the usual focusing-defocusing (Ostwald ripening) of particles, but rather by the formation of ‘magic’ sized clusters. The experimental and theoretical work will help developing an approach to focus size distribution of NPs. The key advantage of the proposed methodology will be that scales more easily for industrial production than the currently used repeated injection techniques.6 References: 1. Talapin, D. V.; Rogach, A. L.; Haase, M.; Weller, H., Evolution of an ensemble of nanoparticles in a colloidal solution: Theoretical study. Journal of Physical Chemistry B 2001, 105, (49), 12278-12285. 2. Voorhees, P. W., The Theory of Ostwald Ripening. Journal of Statistical Physics 1985, 38, (1-2), 231252. 3. Marqusee, J. A.; Ross, J., Kinetics of Phase-Transitions - Theory of Ostwald Ripening. Journal of Chemical Physics 1983, 79, (1), 373-378. 4. Tuinenga, C.; Jasinski, J.; Iwamoto, T.; Chikan, V., In situ observation of heterogeneous growth of CdSe quantum dots: Effect of indium doping on the growth kinetics. Acs Nano 2008, 2, (7), 1411-1421. 5. Dagtepe, P.; Chikan, V.; Jasinski, J.; Leppert, V. J., Quantized growth of CdTe quantum dots; Observation of magic-sized CdTe quantum dots. Journal of Physical Chemistry C 2007, 111, (41), 1497714983. 6. Peng, X. G.; Wickham, J.; Alivisatos, A. P., Kinetics of II-VI and III-V colloidal semiconductor nanocrystal growth: "Focusing" of size distributions. Journal of the American Chemical Society 1998, 120, (21), 5343-5344.
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Figure 1. Time Evolution of the size histogram of a solution containing bimodal distribution of CdSe NPs. The solution consist of 80000 r=1±0.1 nm particles and 2000 r=3.5±0.35 nm particles. The solid black line indicates the critical radius during growth of the NPs.
Figure 2. Time evolution of statistical parameters simulating bimodal size distribution (Black line). When the monomer is added directly to the solution, the parameters evolve according the red line (Injection). When no monomers are added, the parameters evolve according to the green line (Ostwald Ripening). The inset shows the ratio of nucleation rates of Repeated Injection method to the bimodal size distribution method.
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Phase and conductivity dynamics of strontium hexaferrite nanocrystals in a hydrogen gas flow A. A. Fargali1, M. K. Zayed2, M. H. Khedr1* and A. F. Moustafa1 1. Chemistry Department, Faculty of Science, Beni-Sueif University, Beni-Sueif-62111, Egypt. 2. Physics Department, Faculty of Science, Beni-Sueif University, Beni-Sueif-62111, Egypt. The phase and conductivity dynamics of strontium hexaferrite nanocrystals were isothermally studied at different temperatures during a constant flow of hydrogen gas at normal atmospheric pressure. The nanocrystals were prepared by self-flash combustion of acetate precursors. While the formed phase was characterized using XRD, TEM, and optical microscopy after hydrogen exposure, the electrical conductivity was in-situ measured during reduction. The temporal changes in conductivity as well as the formed phases at partial and complete reduction were found to be significantly affected by the operating temperature. Nanocrystals reduced at lower temperatures showed formation of lower oxygen content phases of strontium-iron oxides (SrFe12O19, Sr2Fe2O5, Sr7Fe10O22), and iron oxides (Fe3O4, FeO), while those reduced at higher reducing temperature showed the formation of metallic iron responsible for higher electric conductivity during reduction. Metallic iron nanocrystals of increased sizes were formed at higher reducing temperatures and longer reducing times. Temporal conductivity changes during hydrogen gas flow at different temperatures showed three regions corresponding to removal of surface oxygen, surface reduction, and bulk reduction of the nanocrystals. Nanocrystals reduced at temperatures higher than 400oC showed three reduction regions corresponding to these mechanisms, whereas those reduced at 400oC only two regions could be detected. The activation energies of the oxygen desorption, surface reduction and bulk reduction were found to be 55.5, 40.2, and 44.1 kJ mol-1 respectively. This indicates that oxygen desorption follows a chemical reaction controlled mechanism, while surface and bulk reductions are of combined gas diffusion and interfacial chemical reaction controlled mechanisms. The results obtained from the conductivity measurements were further supported by thermo-gravimetric measurements.
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Electrodic Behavior of Pt Nanoparticles Coupled With CdSe Quantum Dots In Confined Media Clifton Harris Department of Chemistry and Biochemistry University of Notre Dame, Notre Dame, IN E-mail:
[email protected] The electrodic behavior of platinum nanoparticles (NPs), and the nature of the interactions between Pt and CdSe quantum dots (QDs) has been investigated by confining 2.8 nm Pt NPs and 3.4 nm CdSe QDs within heptane/AOT/water reverse micelles. By monitoring the exciton bleaching recovery of CdSe via femtosecond absorption spectroscopy, the electron transfer from CdSe to Pt was found to be completed with an average rate constant of 3.27 × 109 s-1, and an efficiency of 53%. Using methyl viologen (MV2+) as a probe molecule, the role of Pt in the system was determined. Ultrafast oxidation of the MV+. radical (3.1 × 109 s-1), as well as dramatic decreases in the yield of the radical product following steady illumination indicate that Pt acts exclusively as an electron sink. The presence of both Pt and MV2+ in the reverse micelle creates a synergistic effect to enhance the rate constant of the CdSe exciton bleaching recovery by nearly an order of magnitude. The Pt NPs also exhibit the capability of storing and discharging electrons. The nature of the physical and photoinduced metal-semiconductor interactions, and the electrodic behavior of Pt NPs in confined media are potentially important in light energy conversion and photocatalysis.
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Kinetics of acetylene decomposition over reduced strontium hexaferrites catalyst for the production of carbon nanotubes M.H. Khedr*, A.A. Farghali, M.K. Zayed and A.F. Moustafa 1Chemistry Department, Faculty of Science, Beni-Sueif University, Beni-Sueif-62111, Egypt. Carbon nanotubes were synthesised over catalysis of the composition 40SHF (SrFe12O19): 60Al2O3 by the catalytic decomposition of acetylene for different reaction conditions. The kinetics of synthesis of CNTs were investigated through two types of experiments, the first was done at different temperatures. The optimum conditions for the higher yield % were found to be 600°C (367 yield %). The second type of experiments was done at variable decomposition temperature and constant reduction temperature at 600°C. The highest yield % was found at reduction and decomposition temperature 600°C and 700°C respectively (436.9%).
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Plasmonic Field Enhancement of the Exciton-Exciton Annihilation Process in a Poly(paraphenyleneethynylene) Fluorescent Polymer by Ag Nanocubes Adam J. Poncheri,† Mahmoud A. Mahmoud,† Ronnie L. Phillips,‡ and Mostafa A. El-Sayed† Laser Dynamics Laboratory, School of Chemistry and Biochemistry Georgia Institute of Technology, Atlanta, Georgia 30332-0400
[email protected] †Laser Dynamics Laboratory, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400 ‡School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400 Using the Langmuir-Blodgett (LB), a poly(paraphenyleneethynylene) (PPE) fluorescent polymer was assembled on either a quartz substrate (system I) or on the surface of silver nanocube (AgNC) monolayers (system II). The fluorescence intensity of the polymer was studied in system I as a function of the surface density of the polymer sample when deposited on quartz substrates and in system II on the surface coverage of the underlying AgNC monolayers. In system I, a continual increase in the fluorescence intensity is observed as the surface density of excited polymer is increased. In system II, the fluorescence intensity of the polymer first increased until a threshold surface coverage of AgNC was reached, after which it decreased rapidly with increasing surface density in the AgNC monolayer. The exciting light intensity dependence is studied before and after this threshold in system II. The results suggest that one-photon processes were responsible for the increased intensity before the threshold, and two-photon processes were responsible for the rapid decrease in the polymer fluorescence intensity after the threshold. These observations are explained by the increase of the surface plasmon enhancement of the exciting light intensity as the nanoparticle surface coverage is increased. In turn, this increases the polymer absorption rate, which results in a continuous increase in the exciton density as evidenced by an increase in fluorescence intensity. At the threshold, the increased exciton density leads to an increase in the rate of exciton-exciton collisions, which leads to exciton-exciton annihilations. When this phenomenon becomes faster than the rate of fluorescence emission, an intensity decrease is observed. By exploiting the surface plasmon enhancement of absorption processes, we have observed the first exciton-exciton annihilation using a low-intensity Hg-lamp cw-source
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Formation of Copper Nanoparticles by Nanosecond Laser Ablation "
W. A. Ghaly, H. T. Mohsen, Y. A. Badr* and A. I. HelalNuclear Research Center, Atomic Energy Authority, P. O. Box 13759, Cairo, Egypt, National Institute for Laser Enhanced Sciences, Cairo University, Cairo, Egypt E-mail:
[email protected]
*
Preparation of Copper nanoparticles during laser ablation of Copper target in the presence of Nitrogen ambient gas is presented. The experiment was carried out by using the radiation of the pulsed Excimer laser, operating at 193nm, 6ns, 8mJ. Morphology of the formed nanoparticles is studied using Scanning Electron Microscope. High population of spherical shape for the formed nanopaticles is observed. Size distribution of the formed nanoparticles is demonstrated. Digital Imaging Process technique is used to describe the shape of the formed naonparticles.
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Influence of Water on Radical-Molecular Reactions at Surfaces: Perspective from a Study of Water Atmosphere Surface Reaction Models R. J. Buszek and J.S. Francisco Department of Chemistry and Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana E-mail:
[email protected] Hydrogen peroxide plays an integral role in the HOx cycle, as a reservoir for both OH and HO2 radicals. The major chemical removal processes of H2O2 is the oxidation via OH radical, however this process is slow. Sulfuric acid also has slow removal processes, including oxidation via OH radical, leading to the formation of acid rain. The isomerization reaction of the methoxy radical is also of great interest. Methoxy radical is formed in the oxidation of methane and its isomerized into hydroxymethyl radical is a potential source of HO2 radical, however this isomerization is too slow to be relevant. In order to obtain a better overall understanding of the atmospheric chemistry of these reactions, the chemistry in a cloudy atmosphere must also be taken into account, specifically the chemistry happening at the surface of water droplets. Results from high level ab inito computations examining the effect of a model system involving a single water molecule on the oxidation of H2O2 and H2SO4, atmospherically important reactions will be presented. The modeled effects of both water and atmospheric acid catalysis on the isomerization of methoxy radical will also be discussed.
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Synthesis and Characterization of pH-Sensitive PAMPS/PVP Nanogels in Aqueous Media Ayman M. Atta*, Rasha A. M. El-Ghazawy, Reem K. Farag and Shymaa M. Elsaeed Egyptian Petroleum Research Institute, Nasr City 11727, Cairo, Egypt A novel method for preparing poly (2-acrylamido-2-methylpropane sulfonic acid) (PAMPS) and poly (vinylpyrrolidone) (PVP) complex nanogels in PVP aqueous solution was discussed in this article. The PAMPS/PVP complex nanogels were prepared via polymerization of 2-acrylamido-2-methylpropane sulfonic acid monomer in the presence of PVP nanoparticles which formed in water/acetone cosolvent in presence of N,N`-methylenebisacrylamide (MBA) as a crosslinker, N,N,N`,N`-tetramethylethylenediamine (TEMED) and potassium peroxydisulfate (KPS) as redox initiator system. The results of FTIR and 1 HNMR spectra indicated that the compositions of PAMPS/PVP are consistent with the designed structure. TEM micrographs proved that PAMPS/PVP nanogels possess the spherical morphology before and after swelling. These PAMPS/PVP nanogels exhibited pH-induced phase transition due to protonation of PAMPS chains. The properties of PAMPS/PVP nanogels indicate that PAMPS/PVP nanogels can be developed into a pH-controlled drug delivery system.
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Synthesis and Evaluation of Some Hydrophobically Modified Polyacrylamide (HMPAM) Nanolatexes Using Polymerizable Surfactants for Enhanced Oil Recovery Applications E. A. Elsharaky, M. R. Noor El-din, R. A. Elghazawy, N. Kandile and A. M. Alsabagh
Egyptian Petroleum Research Institute, Cairo, Egypt Three series of head type polymerizable surfactants (surfmers) based on maleic anhydride were synthesized. These surfmers have Y shape configuration (with two tails). 1HNMR and FT-IR ascertained the chemical structure of the prepared surfmers. Also, their surface active properties and thermodynamic parameters were estimated at room temperature. The object of this study is to prepare nanosized particles of hydrophobically modified polyacrylamide (HPAM) using the prepared surfmers. HPAM samples are supposed to enhance the rheological properties of their aqueous solutions at low concentrations to find improved systems for enhanced oil recovery applications.
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Characterization of electrophoretically deposited nanocrystalline hydroxyapatite on 316L stainless steel for biomedical applications A. M. Elbasiony(1), N.A. Abdel Ghany (1, #) and Y. A. Elewady (2) (1) Advanced Materials and Nanotechnology Lab., Centre of Excellence for Advanced Sciences, National Research Centre, Dokki, Cairo, Egypt (2) Chemistry Department, Faculty of Science, Mansoura University, Egypt E-mail:
[email protected] Type 316L SS plays a key role in the bone replacement surgery due to its excellent mechanical features, availability at low cost and ease of fabrication. However it fails miserably in vivo conditions due to corrosion related problems. Hence an alternative method on the development of hydroxyapatite (HAP) coatings has been elucidated to impart corrosion resistance of the base metal and ensure biocompatibility of the ceramic on the metal surface. A simple method was attempted for coating hydroxyapatite on 316L stainless steel through electrophoretic deposition (EPD). An ethanolic solution of 0.5M calcium nitrate and 0.5M diammonium hydrogen phosphate at pH 9-11 adjusted to Ca/P molar ratio 1.67 was taken as electrolyte for EPD. The characteristics of the resultant HAP coats on 316L SS have been investigated using: reflectance IR, Scaning electron microscope (SEM) ,X-Ray diffraction, energy dispersive X-Ray and transmition electron microscope (EDAX) the results show the formation of homogeneous coat with Ca/P molar ratio 1.67 wich is compatible with the bone tissue composition and the particle size was in the range 9-20 nm.
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EPRI researching works in the field of natural gas processing Tamer Zaki Department of Catalysis, Petroleum Refining Division, Egyptian Petroleum Research Institute, Cairo, Egypt E-mail:
[email protected] The production of the natural gas is an important and promising investment in Egypt and the world. The presence of acidic gases such as carbon monoxide represented one of the important technical problems in the production process, whereas the CO2 causes decreasing in the calorific value of the fuel in addition to its corrosive disadvantage. On the other hand, mercury has received considerable attention from the environmental engineers due to its high toxicity, a tendency to bio-accumulate and difficulties in its control. The presence of mercury in natural gas became a problem after the catastrophic failure of the aluminum heat exchangers at Skikda in 1973 and the discovery of similar damage at the Groningen Field in the Netherlands which resulted from the amalgamation of elemental mercury in natural gas with the aluminum in heat exchangers, eventually causing physical failure. Volatilized mercury has also been responsible for damaging valuable refinery catalysts, and for contaminating both plant equipment and products. In spite of the presence of many publications on the removal of mercury species from natural gas and wastewater, there is a shortage in the focusing on the mercury problem associated with the petroleum condensate. Such lack in the scientific research may be related to the complexity of the nature of mercury species on the petroleum condensate and petroleum oil. These research projects involve: -Synthesis of Mg-Al and Zn-Al layered double hydroxide (LDH) nanoparticles for selective carbon dioxide adsorption from natural gas. -Removal of mercury compounds from natural gas, condensate and the dehydration waste using nano-adsorbents and metal-organic frameworks (MOFs).
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Poster Session II Wednesday, March 31, 2010 8:00 PM – 10:00 PM 1
Nanotechnologies for the Preparation of Selective Catalysts Ilkeun Lee and Francisco Zaera
Department of Chemistry University of California, Riverside, CA 92521 2
Catalytic Oxidation of CO by O2 Over Nanosized CuO- ZnO System Prepared Under Various Conditions Gamil A.El-Shobaky , Naema S.Yehia, Hassan M.A. Hassan, Abdel Rahman A.A.Badawy Physical Chemistry Department National Research Center Dokki , Cairo , Egypt
3
Synthesis, characterization, and reactivity of magnetically recoverable Pd and Pt nanocatalysts Kevin J. Major and Sherine O. Obare Department of Chemistry and the Nanoscale Science Program University of North Carolina at Charlotte Charlotte, NC 28223
4
ZnO Embedded with Metal Nanoparticles for Visible Range Photocatlytic Applications Ahmed Gera and F.A. Mahmoud* Solid State Physics Dept., National research Center, Dokki , Giza, Egypt
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Conversion of Synthesis Gas to Ethanol via Potassium Promoted Molybdenum Sulfide Catalyst Supported on Activated Carbon Michael Morrill, Thao Nguyen, Pradeep Agrawal, Christopher W. Jones, David Barton, Daniela Ferrari Chemical & Biomolecular Engineering Georgia Institute of Technology Atlanta, GA 30332, USA
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6
Roles of Core Diameter and Silica Content in the Photocatalytic Activity of TiO2/SiO2/Fe3O4 Composite Tarek A. Gad-Allah, Shigeru Kato, Shigeo Satokawa, Toshinori Kojima* Department of Materials and Life Science Seikei University 3-3-1 Kichijoji Kita-machi, Musashino-shi Tokyo 180-8633, Japan
7
Insights into Structure-Sensitive Reactions Using Model Supported Nanoparticles: Reaction Kinetics and PM-IRAS Studies at Near Atmospheric Pressures Sean M. McClure, M. Lundwall, D. Wayne Goodman Department of Chemistry Texas A&M University College Station, TX 77842-3012
8
Enhancement of Olive Mill Wastewater Biodegradation by Homogeneous and Heterogeneous Photocatalytic Oxidation M.I. Badawy, F.El. Gohary, M.Y. Ghaly, , M.E.M. Ali Water Pollution Research Department National Research Centre (NRC) Dokki, Cairo 11312, Egypt
9
Vanadium dioxide nanostructures and nanocomposites as thermal switches Joyeeta Nag Department of Physics and Vanderbilt Institute of Nanoscale Science and Engineering, Vanderbilt University Nashville, Tennessee, USA
10
Characterization and Photocatalytic Properties of Sprayed TiO2 thin Films Doped Cu M. Boshta, M. O. Abou-Helal Solid State Physics Deptartment National Research Center 12311 Dokki, Giza
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Photo-sensitized Formation and Breaking of I-I Bonds at Nanocrystalline TiO2 Interfaces John Rowley, Shane Ardo, and Gerald J. Meyer Departments of Chemistry and Materials Science & Engineering Johns Hopkins University Baltimore, MD 21218
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Catalysis and Gas Sensing Properties of Nanostructured ZnO and Al2O3 Nanobelts and Nanoribbon Grown from the Vapor Phase Osama A. Fouad Central Metallurgical Research and Development Institute Helwan, Egypt
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Breaking Molecular Chemical Bonds in Adsorbed Molecules on a Model Carbon Surface—Alkali-Induced Reactions on Single-Walled Nanotubes Lynn Mandeltort, Michael Büttner, and John T. Yates, Jr. Department of Chemistry University of Virginia Charlottesville, VA 22904
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Synthesis and Characterization of Pure and Doped Titanosilicates for Hydrogen Uptake Nahla Ismail, Islam Hamdy, A. Ghanem, Heba Ezzat Centre of Excellency for Advanced Science Physical Chemistry Department National Research Centre Dokki, Cairo, Egypt
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Building Block Approach for the design and assembly of Zeolite-like MetalOrganic Frameworks (ZMOFs). Ryan Luebke and Mohamed Eddaoudi Department of Chemical Sciences King Abdullah University of Science and Technology Thuwal, Kingdom of Saudia Arabia
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Synthesis, Characterization and Evaluation of New Materials for Hydrogen Uptake M. Madian, N. Ismail, A. A. El-Meligi and M. S. El-Shall Centre of Excellency for Advanced Science Physical Chemistry Department National Research Centre Dokki, Cairo, Egypt
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Innovative Method for the Reduction of Nitrophenols Using Nickel Nanocatalysts Supported on Zeolite-Y Prepared from Egyptian kaolin Doaa El-Mekkawi, Hayam Helmi and Mohamed Selim Physical Chemistry Department National Research Center Dokki. Cairo. Egypt
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Physicochemical, Surface and Catalytic Properties of Nanosized Fe2O3-Cr2O3 System with Different Compositions Gamil A. El-Shobaky* Awad I. Ahmed, Hassan M. A. Hassan and Shaymaa E. El-Shafey Physical Chemistry Department National Research Center Dokki, Cairo, Egypt
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Utilization of Synthetic Zeolite for Removal of Organic Dyes Rasha M. Abd El Wahab Doaa M. El.Mekkawy and M.M.Selim Department of Physical Chemistry National Research Center Cairo, Egypt
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Various Characteristics and Catalytic Activity of Iron (II) Phthalocyanine Immobilized onto Titania- and Vanadia- Pillared Bentonite Clay in in-situ Polymerization of Methyl Methacrylate Salah A. Hassan, Atef S. Darwish, Fatma Z. Yehia, Hamdi A. Hassan, Salwa A. Sadek Department of Chemistry, Faculty of Science Ain Shams University Cairo, Egypt
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EPRI Catalysis Group Activities in the Field of Gas Processing and Petroleum Refining Tamer Zaki Department of Catalysis, Petroleum Refining Division Egyptian Petroleum Research Institute Cairo, Egypt
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Nanotechnologies for the Preparation of Selective Catalysts Ilkeun Lee and Francisco Zaera
Department of Chemistry University of California, Riverside, CA 92521 E-mail:
[email protected] Nano-sized materials have been fundamental in nanoscience and nanotechnology. In catalysis in particular, unexpected activities have been observed and better selectivity control has been possible when using nanoparticles with narrow size distributions and well-defined shapes. In our studies, heterogeneous catalysts have been prepared using platinum nanoparticles with tetrahedral shapes, which expose only (111) facets, or cubic shapes, with only (100) facets. Those particles were initially prepared using colloidal chemistry, and then dispersed and activated on high-surface-area supports. These catalysts have been tested to control selectivity in several catalytic reactions, including cis-trans isomerization in olefins, oxidation of glycerol, and hydrogenation of crotonaldehyde. The nanoparticles have initially been deposited on silica xerogel, but more recent work aims to use better-defined mesoporous supports such as SBA-15 or MCM-41. In separate projects, core-shell architectures and silica coating of supported metal particles via sol-gel chemistry are being explored as a way to enhance the stability of catalysts at higher temperatures.
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Catalytic Oxidation of CO by O2 Over Nanosized CuO- ZnO System Prepared Under Various Conditions Gamil A.El-Shobaky a ,*, Naema S.Yehia b, Hassan M.A. Hassan c, Abdel Rahman A.A.Badawy a a Physical Chemistry Department , National Research Center , Dokki , Cairo , Egypt b Chemistry Department , Faculty of Science , Menoufia University, Shebin El-Kom, Egypt c Chemistry Department , Faculty of Education , Suez Canal University , Suez , Egypt A series of copper and zinc mixed oxides composed of equimolar ratio and treated with 0.05 Al2O3/mol catalyst has been prepared by coprecipitation method using their nitrates in presence of 1 M NaOH solution . The precipitation was carried out at a pH 9.5 and 50 oC. The results revealed that the bulk of various solids consisted of CuO and ZnO having ratios varying between 0.84 and 0.98. On the other hand, the values of surface concentrations of copper and zinc were bigger than those present in the bulk. The values of surface Cu /Zn ratio varied between 1.04 to 1.46 depending on the mode of preparation and calcination conditions. The mixed solids existed as nanocrystalline CuO and ZnO phases. The surface characteristics are strongly dependent on mode of coprecipitation and calcination temperature. The computed SBET values varied between 146 and 23 m2/g depending on mode of coprecipitation and calcination temperature. The increase of calcination temperature of different adsorbents within 300– 400 oC led to a significant progressive decrease in the BET-surface area with subsequent increase in the values of mean pore radius. All adsorbents are mesoporous solids. All prepared solids showed a good catalytic activity in CO oxidation by O2 which proceeds via first order kinetics in all cases. The activation energy of the catalyzed reaction was determined for various solids and the computed values were very small indicating the big catalytic activity of the investigated solids.
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Synthesis, characterization, and reactivity of magnetically recoverable Pd and Pt nanocatalysts Kevin J. Major and Sherine O. Obare Department of Chemistry and the Nanoscale Science Program University of North Carolina at Charlotte, Charlotte, NC 28223
[email protected] Pt and Pd nanoparticles have been extensively used in catalysis and photocatalysis processes, however, in many cases control of particle size or shape is often neglected. We have developed a straightforward one-step wet chemical synthetic approach that produces uniform Pt and Pd nanoparticles in 90% yield. The particles size is controllable within 1 – 5 nm. Particle size was characterized by microscopy, spectroscopy and electrochemistry. With uniform particles at hand, we studied the photocatalytic effects of well-defined Pt nanoparticles. Under specific reaction conditions we find that these Pt particles are effective capacitors, with strong reduction potentials. Recovery of nanocatalysts is also a major challenge to overcome. We demonstrate the reactivity of Pd and Pt nanocatalysts with various small molecules, as well as magnetic recovery of the particles.
Figure 1: TEM image and electrochemical data for Pt nanoparticles.
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ZnO Embedded with Metal Nanoparticles for Visible Range Photocatlytic Applications Ahmed Gera and F.A. Mahmoud* Solid State Physics Dept., National research Center, Dokki , Giza, Egypt E-mail:
[email protected] The design of highly efficient and selective photocatalytic systems that work with minimum cost and sustainable energy for applications that help in reducing global atmospheric pollution and/or degradation of various toxic compounds in pollutant water is one of the most desirable and vital goals in environmental-friendly-catalyst research. The utilization of the nanostructured thin films of semiconductors materials as photocatalysts has attracted a great deal of attention especially for environmental applications. Pure ZnO thin film and ZnO thin film embedded with Ag nanoparticles or Au were obtained by Sol-Gel technique using spin coater on glass, quartz and silicon substrates. The sintering temperature was varied according to the type of substrate; 500 for glass and 750-800 for both of quartz and Silicon. The deposited film was formed from 8-10 layers. The surface morphology of prepared films was studied using SEM where the crystal structure was investigated by XRD and the optical properties were obtained by UV-Vis spectrophotometer. The photocalysis response of the deposited thin solid films was tested in photoreactor and correlated with the preparation parameters. The result of the work is expected to be a significant advance in our capacity to produce simple and sustainable system for water and air cleaning based on nanostructured materials.
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Conversion of Synthesis Gas to Ethanol via Potassium Promoted Molybdenum Sulfide Catalyst Supported on Activated Carbon Michael Morrill1, Thao Nguyen1, Pradeep Agrawal1, Christopher W. Jones1, David Barton2, Daniela Ferrari2 1 Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA 2 Dow Chemical Company, Midland, MI 48674, USA; Dow Benelux, Terneuzen, Netherlands E-mail:
[email protected] As crude oil becomes increasingly scarce, the search for petroleum free routes to chemical products intensifies. The current annual global production for poly(ethylene) is 80 metric tons – the largest of any plastic. Historically, poly(ethylene) has been synthesized via the polymerization of ethene that is most often derived from the steam cracking of petroleum. However, alternative routes to ethene exist such as the dehydration of ethanol. Ethanol is particularly enticing as a feedstock as it can be obtained through the fermentation of sugars or the thermochemical conversion of synthesis gas (H2/CO). Synthesis gas has substantial appeal because it can be a product of biomass and/or coal gasification – two sources of minimal cost. To this end, the conversion of synthesis gas to higher hydrocarbons and alcohols over supported molybdenum sulfide catalysts is a topic of contemporary interest. In this poster, we report the catalytic activity and selectivity of a molybdenum sulfide catalyst supported on Norit activated carbon and promoted by potassium carbonate. The catalyst was prepared by impregnating the activated carbon with molybdenum oxide, addition of potassium carbonate, followed by calcination. The resultant oxide catalyst is sulfided ex-situ in flowing H2S, and then used for the catalytic conversion of synthesis gas to higher alcohols and hydrocarbons in a fixed bed reactor at 310 °C and 1500 psig. The catalyst structure is probed via by XRD, SEM, FT-Raman and FTIR spectroscopy. Reaction products are quantified by online GC. Under the above conditions, the supported molybdenum sulfide catalyst shows high ethanol selectivity but low methanol and hydrocarbon selectivity. Additionally, a carbon monoxide conversion of 19% at a space velocity of 4000h-1 suggests that this catalyst is promising candidate material for ethanol synthesis from synthesis gas. The performance of this catalyst will be compared with the performance of other known catalysts for this reaction.
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Roles of Core Diameter and Silica Content in the Photocatalytic Activity of TiO2/SiO2/Fe3O4 Composite Tarek A. Gad-Allah, Shigeru Kato, Shigeo Satokawa, Toshinori Kojima* Department of Materials and Life Science, Seikei University, 3-3-1 Kichijoji Kita-machi, Musashino-shi, Tokyo 180-8633, Japan Magnetically separable TiO2/SiO2/Fe3O4 composites of different core (Fe3O4) diameters and silica contents have been prepared by sol-gel technique for both silica and titania coatings. Energy dispersive X-ray fluorescence (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), BET surface area analysis and scanning electron microscope (SEM) have been used for characterization of prepared samples. Photocatalytic activity of the prepared samples has been investigated by photodegradation of methyl orange. Obtained results have shown that 25-45 µm core diameter exhibits the maximum activity since it possesses a convenient surface area and light transmittance. Silica content has a significant effect on the activity of composite. Silica content of more than 10 wt% has reduced the catalyst activity because of the increase in particle diameter and reduction of surface area.
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Insights into Structure-Sensitive Reactions Using Model Supported Nanoparticles: Reaction Kinetics and PM-IRAS Studies at Near Atmospheric Pressures Sean M. McClure, M. Lundwall, D. Wayne Goodman Department of Chemistry Texas A&M University, College Station, TX 77842-3012 E-mail:
[email protected] Model catalyst surfaces, consisting of metal nanoparticles supported on a planar oxide support, hold the potential to bridge the material gap between single crystal and technical catalyst studies. When coupled with near atmospheric pressure kinetic and spectroscopic techniques, these well-defined model catalyst surfaces represent a useful approach to provide insights into the structure-activity relationships of industrially relevant reactions. Here, we present recent results of our investigations into the structure sensitivity of the C2H4 hydroformylation reaction (C2H4+CO+H2) at near atmospheric pressures on Rh/SiO2 model catalyst surfaces. Experiments are conducted in a contiguous UHV/high pressure reactor cell system, enabling elevated pressure kinetic and PM-IRAS measurements on Rh/SiO2 surfaces which have been characterized by a variety of surface analytical techniques (e.g. STM, TPD, etc) and probe reactions. As will be presented in detail, kinetic and spectroscopic measurements (PM-IRAS) can provide insights into particle morphology, surface adsorbates and the observed structure-sensitivity (activity and selectivity) during C2H4 hydroformylation at near atmospheric pressures.
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Enhancement of Olive Mill Wastewater Biodegradation by Homogeneous and Heterogeneous Photocatalytic Oxidation M.I. Badawya, F.El. Goharya, M.Y. Ghalyb,!, M.E.M. Alia Water Pollution Research Department, National Research Centre (NRC), Dokki, Cairo 11312, Egypt b Chemical Engineering and Pilot Plant Department, National Research Centre (NRC), Dokki, Cairo, Egypt a
Olive mills wastewater (OMW) is characterized by its high organic content and refractory compounds. In this study, an advanced technology for the treatment of the recalcitrant contaminants of OMW has been investigated. The technique used was either photo-Fenton as homogeneous photocatalytic oxidation or UV/semi-conductor catalyst as heterogeneous photocatalytic oxidation for treatment of OMW. For both the processes, the effect of irradiation time, amounts of photocatalysts and semi-conductors, and initial concentration of hydrogen peroxide has been studied. At the optimum conditions, photo-Fenton process achieved COD, TOC, lignin (total phenolic compounds) and total suspended solids (TSSs) removal values of 87%, 84%, 97.44% and 98.31%, respectively. The corresponding values for UV/TiO2 were 68.8%, 67.3%, 40.19% and 48.9%, respectively, after 80 min irradiation time. The biodegradability expressed by BOD5/COD ratio for treated wastewater was ranged from 0.66 to 0.8 compared to 0.19 for raw wastewater indicating enhancement of biodegradation.
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Vanadium dioxide nanostructures and nanocomposites as thermal switches Joyeeta Nag Department of Physics and Vanderbilt Institute of Nanoscale Science and Engineering, Vanderbilt University, Nashville, Tennessee, USA E-mail:
[email protected]
Devices and structures whose electrical and optical properties can switch in response to thermal loading can create novel functionalities for energy production, use and conservation. Vanadium dioxide (VO2) exhibits a metal-insulator transition near 67oC, characterized by huge changes in electrical resistivity and near-infrared transmission. Its switching response is ultrafast (< 100 fs) when induced with a laser and it is also possible to switch it with the application of electric field. The thermal response of VO2 film as a whole including the transition temperature can be tailored by doping films and nanoparticles with tungsten or titanium. The optical response of subwavelength nanostructures can also be altered by adding plasmonic functionality, for example by synthesizing nanocomposites such as Au::VO2. The plasmonic properties of metal nanoparticles lead to focusing and redistributing eletromagnetic fields and energies at the nanoscale. This transport of optical energy can be modified by altering the dielectric environment of the metal nanoparticles. Using the metal-insulator transition of VO2 we have demonstrated a plasmonic switch that incorporates a thin film of VO2 to control and switch the plasmonic response of gold nanoparticle arrays and nanoscale holes. These twin characteristics of a “smart material” — controllable reconfigurable response to an optical or thermal stimulus — along with their inherent compatibility with silicon technology, renders VO2 suitable for applications in optical switching, space and power-saving optoelectronic modulations, thermal energy management, solar cells and smart window coatings. In this poster, we will discuss the fabrication of VO2 and Au::VO2 thin film, nanoparticles by pulsed laser deposition, with special emphasis on epitaxial film and nanoparticle growth on different planes of sapphire substrates which result in different interesting morphologies. For example, on a-plane of sapphire the VO2 domains grow like oriented nanorods, a topology that is required to produce the difference in phonon scattering along two directions for thermal rectification at the nanoscale. Thermal rectifiers, like electrical rectifiers in electronics, would comprise the essential component of thermal control circuits ranging from nanoscale calorimeters to microelectronic processors to macroscopic refrigerators and energy-saving buildings. Arrays of specially-designed metal nanoparticles like split rings are known to give rise to special plasmonic materials known as metamaterials, structures which have negative permeability and permittivity in a certain range of frequency and can only be man-made. They can show negative refraction leading to superlensing effect and other effects leading to useful redistribution of energies. Other applications of metamaterials include smaller antennas with enhanced radiation power, smart solar power management and shielding structures from earthquakes with acoustic metamaterials. Making broadband metamaterials is a present-day challenge and we will report on a split-ring-combination-based nanoparticle array covered with VO2 which demonstrate considerably increased tunability of metamaterials in the visible-near infrared range of frequency.
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Results obtained in collaboration with Davon W. Ferrara, Andrej Halabica and Richard F. Haglund, Jr. at Vanderbilt University, Tennessee, USA; E. Andrew Payzant and Karren L. More at Oak Ridge National Laboratory, Tennessee, USA; Alex J. Henegar of Eastern Kentucky University, Kentucky, USA; and Stephan A..Pauli and Phillip R. Willmott at Swiss Light Source, Paul Scherrer Institute, Villigen, Switzerland. Research supported by the National Science Foundation (EECS-0801985) and the United States Department of Energy.
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Characterization and Photocatalytic Properties of Sprayed TiO2 thin Films Doped Cu M. Boshta and M. O. Abou-Helal Solid State Physics Dept., National Research Center, 12311 Dokki, Giza E-mail:
[email protected] The present paper describes the properties and photocatalytic application of Cu doped TiO2 thin films on glass substrate by spray pyrolysis technique. The phase structure, and surface properties of the coatings were characterized by using XRD, and AFM respectively. Their optical properties were investigated by UV–vis spectroscopy. The photocatylitic effect of TiO2:Cu on Crystal Violet (CV) dyes measured by spectrophotometer. The absorbance of CV decrease with increasing both the Copper concentration and exposure time.
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Photo-sensitized Formation and BREaking of I-I Bonds at Nanocrystalline TiO2 Interfaces John Rowley, Shane Ardo, and Gerald J. Meyer Departments of Chemistry and Materials Science & Engineering Johns Hopkins University, Baltimore, MD 21218 E-mail:
[email protected]
Recently an order of magnitude increase in solar energy conversion efficiencies from dyesensitized photovoltaic cells has been realized.1,2 These solar cells are based upon mesoporous thin films of nanocrystalline (anatase) TiO2 sensitized to visible light with inorganic coordination compounds that serve as dyes. Under simulated sunlight conditions, solar-to-electrical power conversion efficiencies of 11.4% have been confirmed. The sensitized nanocrystalline materials have an enormous surface area, a long effective pathlength, and a high photoconductivity that affords both spectroscopic and photoelectrochemical characterization of interfacial charge transfer processes. Iodide oxidation to form I-I bonds is key to sensitizer regeneration in dyesensitized solar cells. Mechanistic details of how iodide oxidation yields the I-I bonds present in I2-• and I3- reaction products remain speculative.3 Likewise, charge recombination to the iodide oxidation products is thought to lower the solar energy conversion yield but remain poorly understood. In this presentation, mechanistic details of photoinduced iodide oxidation and reduction at nanocrystalline TiO2 interfaces will be described. Oxidation of iodide was initiated through direct excitation of iodide, band gap excitation of the semiconductor, and/or sensitized to visible light with ruthenium polypyridyl compounds. The results of this study provide strong evidence that I3- acts as the principal electron acceptor at illuminated sensitized nanocrystalline interfaces and that under simulated sunlight conditions interfacial charge recombination is strongly dependant on the quasi-Fermi level of the TiO2. Unwanted recombination to I2-• has previously been proposed to lower the efficiency of dye-sensitized solar cells and this data shows that a fast disproportionation reaction effectively prevents recombination under these conditions.4 Interfacial energetics, quantified through spectro-electrochemical measurements, provide further insights into the mechanisms of electron transfer reactions at semiconductor nanocrystallites and the efficiencies of dye sensitized solar cells. Our experimental findings provide new molecular level insights into the mechanisms of heterogeneous electron transfer at nanocrystalline semiconductor interfaces that have broad implications for energy, petrochemicals and environmental applications. References: 1.
A Low-Cost, High-Efficiency Solar Cell Based on Dye-Sensitized Colloidal TiO2 Films. O’Regan, B.; Gratzel, M.; Nature (1991) 353 737-740 2. Light-Induced Redox Reactions in Nanocrystalline Systems. Hagfeldt, A.; Gratzel, M.; Chem. Rev. (1995), 95, 49-68 3. Evidence for Iodine Atoms as Intermediates in the Dye Sensitized Formation of I-I Bonds. Gardner, J. M.; Giaimuccio, J. M.; Meyer, J. G.; J. Am. Chem. Soc. (2008) 130(51): 17252-17253 4. Reduction of I2/I3- by Titanium Dioxide. Rowley, J. G.; Meyer, G. J. J. Phys. Chem. C. (2009) 113(43): 17444-17447.
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Catalysis and Gas Sensing Properties of Nanostructured ZnO and Al2O3 Nanobelts and Nanoribbon Grown from the Vapor Phase Osama A. Fouad Central Metallurgical Research and Development Institute, (CMRDI), P.O. Box: 87 Helwan 11421, Helwan, Egypt E-mail:
[email protected] Vapor growth of nanostructured materials is a promising process for the fabrication of the materials in pure and good quality forms. The driving forces for growth of these nanostructures were found to be vapor density or supersaturation, temperature, pressure and place of deposition from the source materials. For these materials, catalytic, thermal, chemical and other properties depend mainly on the particle size and shape. The large number of surface and edge atoms provides active sites for catalyzing surface-based reactions. Research in this area is motivated by the possibility of designing nanostructured materials that are stable, selective and active at low temperatures. The high surface-to-volume ratio of the nanobelts, nanoribons, nanorods, nanowires and nanotubes give an advantage of using such structures in many processes and device fabrication. Although, tin oxide has been used commercially for gas sensing application, zinc oxide has been extensively studied as a possible promising candidate. Moreover, alumina powder has been used as support of many catalysts. This presentation will highlights on some results that obtained so far by our group on synthesis, characterization of ZnO and Al2O3 nanostructures that have designed and tailored from the vapour phase and has been tested as for catalytic and gas sensing applications.
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Breaking Molecular Chemical Bonds in Adsorbed Molecules on a Model Carbon Surface—Alkali-Induced Reactions on Single-Walled Nanotubes Lynn Mandeltort, Michael Büttner, and John T. Yates, Jr. Department of Chemistry, University of Virginia Charlottesville, VA 22904 E-mail:
[email protected] Li Xiao and J. Karl Johnson Department of Chemical Engineering, Pittsburgh University Pittsburgh, PA 15236 Single-walled carbon nanotubes (SWNTs) exhibit superior physical adsorption properties due to their high surface area and their internal sites, which strongly bind molecules by van der Waals forces. Temperature programmed desorption has been used to detect molecules in the various internal and external adsorption sites of 1.36 nm diameter SWNTs. We have found that Li atoms ionize on the SWNT surface and enhance the binding of non-polar molecules such as n-heptane by means of polarization in the vicinity of the Li+ ions. Molecules containing a C-Cl bond (such as CH3Cl) experience dissociative adsorption in the presence of Li, producing CH3 radicals and LiCl. The CH3 radicals preferentially bind to defect sites on the nanotube wall while LiCl and its dimer desorb at about 675 K. Thus by doping the nanotubes with Li, it is possible to make them chemically active and effective adsorbents for destruction of toxic halogen-containing molecules. Work supported by the Defense Threat Reduction Agency under Contract HDTRA1-09-1-0008
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Synthesis and Characterization of Pure and Doped Titanosilicates for Hydrogen Uptake Nahla Ismail, Islam Hamdy, A. Ghanem, Heba Ezzat Centre of Excellency for Advanced Science Physical Chemistry Department National Research Centre, Dokki, Cairo, Egypt Natural silica source from Red Sea Desert - Egypt was successfully employed as a starting precursor for hydrothermal preparation of titanosilicate types natisite and sitinakite. Interestingly the structure of the starting precursor of the silica source plays a role in controlling the identity of the type of the produced titanosilicate. ETS-4, vanadium ETS-4 (V-ETS-4), natisite, vanadium natisite (V-natisite), sitinakite.. The samples were capable of adsorbing 2-2.3 wt% at -193°C and 20bar applied hydrogen pressure. The dense natisite structure prepared by natural silica (n-SiO2) exhibited higher hydrogen adsorption capacity than that measured for solid prepared by commercial silica (k-SiO2).
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Building Block Approach for the design and assembly of Zeolite-like MetalOrganic Frameworks (ZMOFs). Ryan Luebke and Mohamed Eddaoudi Department of Chemical Sciences King Abdullah University of Science and Technology Thuwal, Kingdom of Saudia Arabia
[email protected] The molecular building block (MBB) approach has emerged as a powerful strategy in the design and construction of solid-state materials. MBBs have been utilized previously as components in the design and synthesis of novel metal-organic frameworks (MOFs), most based on the assembly of metal-carboxylate clusters and polytopic organic ligands of various shapes. Here we present the use of the MBB approach in the rational assembly of pre-designed polytopic organic linkers and hetero-coordinated single metal, MNxOy -type, clusters into new zeolite-like metal-organic frameworks (ZMOFs) with extra-large cavities. Porous anionic ZMOFs, rho-ZMOF, sodZMOF and usf-ZMOF, have been constructed by metal-ligand directed assembly of rigid and directional tetrahedral building units, InN4 synthesized in-situ, and directional and rigid bis-(bidentate) organic ligands in the presence of different structure directing agents (SDAs). The design strategy, synthesis, structure, porosity, and their inclusion and sensing chemistry will be discussed. Figure 1: Single-Crystal structure of rho-ZMOF composed of (a) eight-coordinated MBBs which can be viewed as a 4connected TBUs (b), (c) the ImDC ligand, linked to In forming the 8-coordinated MBB. (d) a fragment of the rhoZMOF. The large yellow spheres represent the largest sphere that would fit in the a-cavities without touching the van der Walls atoms of the framework
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a)
d)
b)
c)
Synthesis, Characterization and Evaluation of New Materials for Hydrogen Uptake 1
M. Madian1, N. Ismail1, A. A. El-Meligi1 and M. S. El-Shall2 Centre of Excellency for Advanced Science, Physical Chemistry Department National Research Centre, Dokki, Cairo, Egypt 2 Department of Chemistry, Virginia Commonwealth University Richmond, VA 23284-2006
Research on new materials to be tested to store hydrogen is of great interest. Iron phosphorus trisulphide FePS3 is related to the chalcogenides characterized by layered structure. FePS3 powder has been prepared with solid state reaction and heated up to 650°C using two different heating rates 1°C/min and 40°C/min. The results showed that the FePS3 produced with slow heating rate is highly ordered single crystalline phase while powder produced with the fast heating rate is poly crystalline phase. The surface morphology, the grain size and interlayer distance are influenced by the heating rate used for preparation. Hydrogen adsorption isotherms showed linear relationship with increasing pressure. The materials showed hydrogen storing ability up to 2.2 wt% and3.2 wt.% at77 K and hydrogen pressure of 20 and 30 bar, respectively. Graphene has been prepared by Hummer method by exfoliation and reduction of graphide oxide using hydrazine hydrate. The graphene sheets produced is able to adsorb 0.28 wt.% hydrogen at 273K and 20 bar. At 77K and the same applied pressure, the sample sucks 3.4 wt.% hydrogen. Metal organic frame work MIL101 was prepared hydrothermally at 220 oC. MIL101 displays hydrogen storage capacity 4.4wt.% at 77K and 20 bar. Doping of 10% Pd and 10% Ni with MIL101 did not affect its hydrogen storage capacity.
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Innovative Method for the Reduction of Nitrophenols Using Nickel Nanocatalysts Supported on Zeolite-Y Prepared from Egyptian kaolin Doaa El-Mekkawi, Hayam Helmi and Mohamed Selim Physical Chemistry Dept., National Research Center Dokki. Cairo. Egypt The reduction of ortho and para nitrophenols into the corresponding aminophenols has been proceeded via a new efficient catalytic reduction procedure. Nickel nanocatalysts supported on zeolite Y prepared from Egyptian kaolin has been used in the presence of hydrazine hydrate molecules which first decompose to give hydrogen atoms. These hydrogen atoms reduce the nickel ions exchanged inside the zeolite cages. This allows the formation of nickel atoms in the nanoscale size. Further decomposition of the hydrazine hydrate on the nickel atom surfaces yields nascent hydrogen atom that will efficiently reduce the nitro groups. In this work many techniques such as XRD, IR, TEM, UV-Visible absorption spectroscopy, and atomic absorption measurements have been used. XRD analysis confirms that zeolite Y retained its framework after nickel exchange processes. The atomic absorption measurements were used to determine the amount of nickel ions exchanged in zeolite. TEM shows the formation of nano nickel atoms inside the zeolite cages. IR analysis confirms the appearance of the characteristic peaks of only ortho or para aminophenols. UV-Visible absorption measurements have been used to follow up the disappearance of the nitro compounds as well as the estimation of the conversion percentage. Catalyst recovery and factors affecting the reduction reaction such as phenol concentration, pH, catalyst loading and temperature have been studied. The obtained data and kinetic results indicate that at a given experimental conditions, the conversion percentage reaches 100% within few minutes. Comparing the results to the previously published studies, it can be concluded that this method is more economic, faster and more efficient.
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Physicochemical, Surface and Catalytic Properties of Nanosized Fe2O3-Cr2O3 System with Different Compositions Gamil A. El-Shobaky,1* Awad I. Ahmed, 2 Hassan M. A. Hassan3 and Shaymaa E. El-Shafey1 1. Physical Chemistry Department, National Research Center, Dokki, Cairo, Egypt 2. Faculty of Science, Chemistry Department, Mansoura University, Mansoura, Egypt 3. Faculty of Science, Chemistry Department, Suez Canal University, Suez, Egypt Ferric and chromic mixed oxides solids having different compositions were prepared by thermal decomposition of their mixed hydroxides at 400-600°C. The mixed hydroxides were obtained by coprecipitation of mixed ferric and chromic nitrates solution using NH4OH solution at 50°C and a pH= 8. The obtained solids were characterized by using TGA, DTA, XRD, N2 adsorption at -196°C and catalysis of CO oxidation by O2 at 200-300°C. The results revealed that all mixed oxides calcined at 400°C consisted of amorphous solids and turned to #-Fe2O3 phase upon heating at 500 and 600°C. The average crystallite size of #-Fe2O3 varried between 21 and 35 nm. The SBET of different solids decreased by increasing the calcination temperature. The decrease was, however, more pronounced upon increasing the heating temperature from 400 to 500°C. The SBET, in general, increases by increasing the Cr2O3 content. All adsorbents investigated are mesopores solids. The catalytic activity was found to increase, also, by increasing the Cr2O3 content. The computed values of apparent activation energy of CO oxidation by O2 carried out over different solids were relatively small indicating an advanced catalytic activity of all solids investigated.
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Utilization of Synthetic Zeolite for Removal of Organic Dyes Rasha M. Abd El Wahab, Doaa M. El.Mekkawy, and M.M.Selim Department of Physical Chemistry National Research Center, Cairo, Egypt The removal performance of highly coloured soluble organic pollutants in water has been investigated. Comparative adsorption studies of organic dyes on commercially zeolite X and zeolite Y powder prepared from Egyptian kaolin have been introduced. Brilliant blue, brilliant black, eriochrome black T and ponceau 3R were introduced as models for organic pollutants of different structures. XRD, DTA, atomic absorption spectroscopy and UV/visible spectroscopic measurements have been used in this work. For comparison the properties of the synthetic zeolites and commercial grade zeolites, such as elemental composition, thermal stability and cation exchange capacity using XRD, DTA and atomic absorption spectroscopy, respectively were investigated. UV/visible spectroscopic measurements have been used to determine the amount of adsorbed dyes on zeolite surfaces. The adsorption capacities for both batch method and fixed-bed reactors were recorded. The influential parameters, such as initial pH value of the solution, temperatures, adsorbate concentration and ion exchange on the adsorption process were studied. The suitability of Langmuir and Freundlich isotherms to the equilibrium data was investigated in the solid-liquid system. In all the adsorption experiments, the variation of adsorption capacities were recorded and explained in terms of both zeolite behaviour and dyes structures. Attempts to regenerate the adsorbents were also made and the adsorptive properties of the recovered zeolite have been provided.
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Various Characteristics and Catalytic Activity of Iron (II) Phthalocyanine Immobilized onto Titania- and Vanadia- Pillared Bentonite Clay in in-situ Polymerization of Methyl Methacrylate: An attempt to synthesize a novel polymer / iron phthalocyanine / pillared clay nano composite Salah A. Hassan1, Atef S. Darwish*1, Fatma Z. Yehia2, Hamdi A. Hassan1, Salwa A. Sadek1 1 Department of Chemistry, Faculty of Science, Ain Shams University, Cairo, Egypt 2 Department of Petrochemical Technology, Egyptian Petroleum Research Institute, Cairo, Egypt In the present study, the pure bentonite clay has been modified by pillaring with titania and vanadia (Ti-PILB and V-PILB). Iron (II) phthalocyanine complex (FePc) was immobilized in 0.5 wt% loading on the modified bentonite supports. Structural characteristics of the various samples were investigated through XRD, FTIR, TGA, and ICPEDX techniques. Textural and morphological characteristics were estimated from low-temperature adsorptiondesorption isotherms of N2, pore size distribution analysis and SEM. Dispersion parameters of FePc molecules were determined from H2 chemisorption isotherms. Acid-base properties were studied by potentiometric titration method and cation exchange capacities were determined. Catalytic activity of the prepared catalyst samples was examined in the in-situ bulk polymerization of methyl methacrylate. The kinetic results were discussed in correlation with the various characteristics to determine the role of acid sites and FePc molecules in the polymerization mechanism. !w and !n values of the polymers produced decreased, according to the used support, in the order: Ti-PILB > ATTB > V-PILB, exactly in the same decreasing order of the chain transfer constant (CT). This indicated more contribution of FePc. A possibility of living polymerization mechanism, within the role of FePc in the re-initiation of the dormant polymer molecules, was confirmed. A new approach for the synthesis of PMMA / 0.5 wt % FePc / modified bentonite composites was provided through a number of characterization techniques and via different proposed schemes. The modified bentonite layers were partially exfoliated on the PMMA base. The PMMA layered structure was arranged in a decreasing order, according to the modified bentonite, V-PILB > Ti-PILB > ATTB, where nano-sized vanadia particles (25 nm) were involved with better dispersion and well homogeneity.
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EPRI Catalysis Group Activities in the Field of Gas Processing and Petroleum Refining Tamer Zaki Department of Catalysis, Petroleum Refining Division, Egyptian Petroleum Research Institute, Cairo, Egypt E-mail:
[email protected]
The catalysis group in the Egyptian Petroleum Research Institute (EPRI) has been starting a huge and miscellaneous researching works since few years. The aim of this presentation is bringing to light a part of the researching activities of this group that concerned with the applications of the nanomaterials in the field of gas processing and petroleum refining. The topics of these research projects include:
- Synthesis of nano- and layered nano-proveskite for the oxidative coupling of the methane (OCM). - Synthesis of Mo-W oxide nanocatalysts for the petroleum condensate isomerization. - Synthesis of $-alumina based nanocatalysts for alcohols dehydration. - Synthesis of high surface area #-alumina. - Comparative study for the desulfurization of diesel fuel via oxidation-extraction and adsorption techniques. - Enhancement the biodesulfurization (BDS) of petroleum distillates by using magnetic nanoparticles. - Bio-remediation of petroleum spills by using biocatalysts coated with photo-catalytic magnetic nanoparticles. - Synthesis of Mg-Al and Zn-Al layered double hydroxide (LDH) nanoparticles for selective carbon dioxide adsorption from natural gas. - Removal of mercury compounds from natural gas, condensate and the dehydration waste using nano-adsorbents and metal-organic frameworks (MOFs).
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US CONTACTS Faisal M. Alamgir Materials Science and Engineering Georgia Institute of Technology Atlanta, GA 30332-0245 Phone: (404) 385-3263 E-mail:
[email protected] Robert Buszek Department of Chemistry Purdue University West Lafayette, IN 47907 Phone: (765) 494-5244 E-mail:
[email protected] Pinar Dagtepe Department of Chemistry Kansas State University Manhattan, KS 66506, USA Phone: (785) 395-4796 E-mail:
[email protected] Erik Dreaden Laser Dynamics Laboratory, School of Chemistry and Biochemistry Georgia Institute of Technology Atlanta, GA 30332, USA Phone: (404) 894-4009 E-mail:
[email protected] Mohamed Eddaoudi Department of Chemistry University of Florida Tampa, FL 33620-5250 Phone: 813-974-9622 E-mail:
[email protected] Mostafa A. El-Sayed Laser Dynamics Laboratory, School of Chemistry and Biochemistry Georgia Institute of Technology Atlanta, GA 30332-0400 Phone: 404-894-0292 E-mail:
[email protected] M. Samy El-Shall Departments of Chemistry and Chemical Engineering Virginia Commonwealth University Richmond, VA 23284, 2006 Phone: 804-828-3518 E-mail:
[email protected] 129
Sherrie R. Elzey Department of Chemical & Biochemical Engineering University of Iowa Iowa City, IA 52242, USA Phone: (641) 831-3975 E-mail:
[email protected] Christopher Evans Department of Chemistry University of Rochester Rochester, NY 14627, USA Phone: (585) 750-6882 E-mail:
[email protected] Joseph S. Francisco Department of Chemistry and Department of Earth and Atmospheric Science Purdue University West Lafayette, Indiana 47907-2084 Phone: 765-494-7851 Email:
[email protected] Bruce C. Gates Departments of Chemical Engineering and Materials Science University of California Davis, CA 95616-5294 Phone: 530-752-3953 E-mail:
[email protected] Wayne Goodman Department of Chemistry Texas A&M University College Station, TX 77843-3012 Phone: 979-845-0214 E-mail:
[email protected] Vicki H. Grassian Departments of Chemistry & Chemical and Biochemical Engineering University of Iowa Iowa City, IA 52242-1294 Phone: 319-335-1392 E-mail:
[email protected] Clifton Harris Department of Chemistry and Biochemistry University of Notre Dame Notre Dame, IN 46556, USA Phone: (574) 631-9507 E-mail:
[email protected] 130
Rebecca Hayoun Department of Chemistry University of Washington Seattle, WA 98195, USA Phone: (206) 616-4212 E-mail:
[email protected] Natalie Herring Department of Chemistry Virginia Commonwealth University Richmond, VA 23284, USA Phone: (804) 827-1222 E-mail:
[email protected] Puru Jena Department of Physics Virginia Commonwealth University Richmond, VA 23284-2000 Phone: 804-848-8991 E-mail:
[email protected] Prashant V. Kamat Departments of Chemistry & Biochemistry Department of Chemical and Biomolecular Engineering, and Radiation Laboratory University of Notre Dame Notre Dame IN 46556 Phone: 574-631-5411 E-mail:
[email protected] Ilkeun Lee Department of Chemistry University of California, Riverside Riverside, CA 92521, USA Phone: (951) 827-5736 E-mail:
[email protected] Ryan Luebke Department of Chemical Science King Abdullah University of Science and Technology Thuwal 23955-6900, Kingdom of Saudi Arabia Phone: 0553422636 E-mail:
[email protected] Kevin Major Department of Chemistry and the Nanoscale Science Program University of North Carolina at Charlotte Charlotte, NC 28223, USA Phone (704) 687-4765 E-mail:
[email protected] 131
Lynn Mandeltort Department of Chemistry University of Virginia Charlottesville, VA 22904, USA Phone: (434) 924-3344 E-mail:
[email protected] Sean Michael McClure Department of Chemistry Texas A&M University College Station, TX 77842, USA Phone: (979) 845-2011 E-mail:
[email protected] Omar F. Mohammed Physical Biology Center for Ultrafast Science and Technology Arthur Amos Noyes Laboratory of Chemical Physics California Institute of Technology Pasadena, CA 91125, USA Phone: (626) 395-2279 E-mail:
[email protected] Michael Robert Morrill School of Chemical and Biomolecular Engineering Georgia Institute of Technology Atlanta, GA 30318, USA Phone: (801) 494-7340 E-mail:
[email protected] Joyeeta Nag Department of Physics Vanderbilt Institute of Nanoscale Science and Engineering Vanderbilt University Nashville, TN 37235, USA Phone: (615) 414-0340 E-mail:
[email protected] Adam Poncheri Laser Dynamics Laboratory, School of Chemistry and Biochemistry Georgia Institute of Technology Atlanta, GA 30332, USA Phone: (404) 894-4009 E-mail:
[email protected]
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John G. Rowley Department of Chemistry Johns Hopkins University Baltimore, MD 21218, USA Phone: (443) 928-7374 E-mail:
[email protected] Mark G. White Dave C. Swalm School of Chemical Engineering James Worth Bagley College of Engineering Box 9595, MS 39762 Phone: 662-325-2480 E-mail:
[email protected] John Yates Department of Chemistry University of Virginia Charlottesville, VA 22904-4319 Phone: 434-924-7514 E-mail:
[email protected] Francisco Zaera Department of Chemistry University of California, Riverside Riverside, CA 92521 Phone: 951-827-5498 E-mail:
[email protected]
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EGYPTIAN CONTACTS Ahmed Kadry Aboul-Gheit Catalysis Division Egyptian Petroleum Research Institute (EPRI) Cairo, Egypt E-mail:
[email protected] Ayman M. Atta Egyptian Petroleum Research Institute Nasr City 11727, Cairo, Egypt M.I. Badawy Water Pollution Research Department National Research Centre Dokki, Cairo 11312, Egypt M. Boshta Department of Solid State Physics National Research Center 12311 Dokki, Giza E-mail:
[email protected] Magdah Dawy National Research Center Dokki, Cairo, Egypt E-mail:
[email protected] Ahmed A. El-Moneim Egyptian-Japanese University of Science and Technology Borg El Arab, Alexandria, Egypt National Research Centre, Giza, Egypt E-mail:
[email protected] A. M. Elbasiony Advanced Materials and Nanotechnology Lab Centre of Excellence for Advanced Sciences National Research Centre Dokki, Cairo, Egypt E-mail:
[email protected] Doaa El-Mekkawi Department of Physical Chemistry National Research Center Dokki. Cairo. Egypt
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E. A. Elsharaky Egyptian Petroleum Research Institute Cairo, Egypt Gamil A. El-Shobaky Department of Physical Chemistry National Research Center Dokki, Cairo, Egypt M. El Sukkary Petrochemicals Division Egyptian Petroleum Research Institute (EPRI) Cairo, Egypt E-mail:
[email protected] A.A. Elzatahry Institute of Advanced technology and New materials, Mubarak City for Scientific Research and technology applications New Borg Alarab, Alexandria, Egypt I. K. El Zawawi Solid State Physics Department National Research Center Dokki, Cairo, Egypt E-mail:
[email protected] A. A. Fargali Chemistry Department, Faculty of Science Beni-Sueif University Beni-Sueif-62111, Egypt Osama A. Fouad Central Metallurgical Research and Development Institute Helwan, Egypt E-mail:
[email protected] Rabei M. Gabr Chemistry Department Assiut University, Assiut, Egypt E-mail:
[email protected] Tarek A. Gad-Allah Department of Materials and Life Science Seikei University 3-3-1 Kichijoji Kita-machi, Musashino-shi Tokyo 180-8633, Japan 135
Ahmed Galal Department of Chemistry, Faculty of Science University of Cairo, Postal Code 12613, Giza-Egypt Email:
[email protected] Ahmed Gera Department of Solid State Physics National research Center Dokki , Giza, Egypt W. A. Ghaly Nuclear Research Center, Atomic Energy Authority National Institute for Laser Enhanced Sciences Cairo University Cairo, Egypt E-mail:
[email protected] Hassan M. A. Hassan Chemistry Department, Faculty of Science Suez Canal University, Suez, Egypt E-mail:
[email protected] Salah A. Hassan Department of Chemistry, Faculty of Science Ain Shams University Cairo, Egypt Nahla Ismail Centre of Excellency for Advanced Science Department of Physical Chemistry National Research Centre Dokki, Cairo, Egypt E-mail:
[email protected] A. B. Kashyout Advanced Technology and New Materials Research Institute Mubarak City for Scientific Research and Technology Applications (MuCSAT) New Borg El-Arab City, P.O. Box 21934, Alexandria, Egypt E-mail:
[email protected] Abd El Rahman S. Khder Department of Chemistry, Faculty of Science El-Mansoura University, El-Mansoure, Egypt E-mail:
[email protected] Mahmoud H. Khedr Nanomaterials Unit, Faculty of Science, Benisuef University Benisuef, Egypt E-mail:
[email protected] 136
M. Madian Centre of Excellency for Advanced Science Department of Physical Chemistry National Research Centre Dokki, Cairo, Egypt Mona B. Mohamed National Institute of Laser Enhanced Science (NILES) Cairo University, Giza, Egypt E-mail:
[email protected] Magdy M. Nasrallah Department of Petroleum and Energy Engineering The American University in Cairo, Cairo, Egypt Email:
[email protected] S. Negm Department of Physics and Mathematics Faculty of Engineering, (Shoubra) Benha University Egypt Abd EL-Aziz A Said Chemistry Department, Faculty of Science Assiut, University, Assiut, Egypt E-mail:
[email protected] R. Seoudi National Research Center Dokki, Cairo, Egypt Gamil A.El-Shobaky Department of Physical Chemistry National Research Center Dokki, Cairo, Egypt Hassan Talaat Faculty of Science, Ain Shams University, Cairo, Egypt E-mail:
[email protected] Rasha M. Abd El Wahab Department of Physical Chemistry National Research Center Dokki, Cairo, Egypt Mohamed I. Zaki Chemistry Department, Faculty of Science, Minia University, El-Minia 61519, Egypt E-mail:
[email protected] 137
Tamer Zaki Department of Catalysis, Petroleum Refining Division Egyptian Petroleum Research Institute Cairo, Egypt E-mail:
[email protected]
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