Graphene has attracted great interest for a fundamental understanding of its unique structural and electronic properties and also 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 facile and scalable chemicaland physical reduction methods for the synthesis of chemically and laserconverted graphene, as well as for metal and semiconductor nanoparticles dispersed on graphene.This talk will address two novel aspects of graphene research dealing with the efficient photothermal energy conversion by graphene and nanocatalysis by metal-graphene nanocomposites. In the first aspect, the observed photothermal effects leading to a significant increase in the temperature of the solution suggests that metal-graphene nanocomposites could be promising materials for the efficient conversion of solar energy into usable heat for a variety of thermal, thermochemical, and thermomechanical applications.In the second aspect, we demonstrate the excellent catalytic activity of Pd-graphene nanocomposites for the carbon-carbon Suzuki and Heck cross coupling reactions.These reactions have been extensively used for the assembly of complex organic molecules for a wide variety of applications with considerable impact on the chemical and pharmaceutical industries. The exceptional activity and stability of the Pd-graphene catalyst and the development of other novel metallic and bimetallic catalysts supported on graphene will be discussed.Finally, we will present the application of graphene as a catalyst support for the Fischer-Tropsch Synthesis (FTS), which is increasingly attracting global interests as a consequence of environmental demands, technological developments, and changes in fossil energy reserves. The simultaneous chemical reduction of the metal precursors and graphene oxide in water under microwave irradiation allows the deposition of well-dispersed metal nanoparticles on the defect sites of the graphene nanosheets. The FeK-graphene catalyst exhibits high activity and selectivity towards higher products with excellent stability and recyclability. The exceptional activity and stability of the FTS-graphene catalysts will be presented and discussed.
M. Samy El Shall (Virginia Commonwealth University) received his B.S. and M.S. degrees from Cairo University, and a Ph.D. from Georgetown University. He did postdoctoral research in nucleation and clusters at UCLA. His research interests are in the general areas of molecular clusters, nucleation phenomena, nanostructured materials, graphene and nanocatalysis for energy and environmental applications. He has published over 210 refereed papers and review chapters, and he holds eight US patents on the synthesis of nanomaterials, nanoalloys, nanoparticle catalysts, graphene, and graphene-supported catalysts. Dr. El-Shall received the Outstanding Faculty Award of Virginia in 1999; the Distinguished Research Award from the Virginia Section of the American Chemical Society in 2009; the Innovative Research Award from the Society of Automotive Engineering (SAE) in 2009; and the VCU Distinguished Scholarship Award in 2011. He was elected as a Fellow of the American Physical Society in 2012, and was selected as a Jefferson Science Fellow at the U.S. Department of State for 2012-2013.
University of Illinois at Urbana-Champaign