Abstract:
We provide atomic-scale structural and chemical-state information for oxide supported catalysts with in situ x-ray scattering and spectroscopy methods. X-ray standing wave (XSW) analysis produces 3D atomic maps of the catalytic species. The morphology of the supported catalytic structures (e.g., noble metal cluster formation by atomic layer deposition (ALD)) is measured using atomic force microscopy (AFM) and grazing incidence small angle X-ray scattering (GISAXS). The chemical oxidation state is measured by X-ray photelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). By this combination we are able to correlate interfacial chemical state changes with atomic-scale structural changes induced by reduction and oxidation (redox) reactions.
“Redox driven crystalline coherent-incoherent transformation for a 2 ML VOx film grown on ？-TiO2(110)”, C.-Y. Kim, J. W. Elam, P. C. Stair and M. J. Bedzyk, J. Phys. Chem C 114, 19723-19726 (2010).
“Direct Atomic-Scale Observation of Redox-Induced Cation Dynamics in an Oxide-Supported Monolayer Catalyst: WOX/α-Fe2O3(0001)”, Z. Feng, C.-Y. Kim, J. W. Elam, Q. Ma, Z. Zhang, M. J. Bedzyk, J. Am. Chem. Soc. 131, 18200-18201 (2009).
报告人简介：
Michael Bedzyk (born 1951) is a Professor of Materials Science & Engineering and Physics & Astronomy at Northwestern University (NU) in Evanston, Illinois USA. (Just outside Chicago.) Prior to his arrival to Northwestern in 1991, he earned a PhD in Physics from the State University of New York at Albany (1982), was a postdoc at DESY in Hamburg, Germany till the end of 1984 and was then a staff scientist/adjunct professor at Cornell University. He presently serves at Northwesten as the founding co-chair of the Applied Physics Program, the co-director of the Synchrotron Research Center, and is the in-coming chair for the Department of Materials Science and Engineering. Bedzyk’s area of research is X-ray Interfacial Science, where he has developed novel X-ray probes for atomic-scale characterization of surfaces, interfaces, ultra-thin-films and nanostructures. Most of his experiments make use of the high X-ray brightness from the Advanced Photon Source at Argonne National Laboratory. (Also in the Chicago area.) He is a member of several scientific societies, a Fellow of the American Physical Society and was awarded the Warren Award for Diffraction Physics in 1994 from the American Crystallographic Association.
联系人：金奎娟 研究员（82648099）
报告邀请人：曹立新 研究员 (82648117)