Tuesday, 15 October, 2013
Dr. Zili Wu
Research & Development Staff
Chemical Science Division and Center for Nanophase Materials Sciences
Oak Ridge National Laboratory
"Shape Effect in Catalysis: Nanoshapes as Catalyst and Catalyst Support"
Heterogeneous catalysis takes place on the surface of catalytic materials and undoubtedly the surface structure plays an essential role in catalysis. Establishing the structure-catalysis relationship is the Holy Grail in fundamental catalysis research and the basis or designing better catalytic materials. However, the structural complexity and heterogeneity of traditional catalysts prevents a full understanding of the interplay between the surface structure and catalytic behaviors.
Recent advances in nanomaterials synthesis make it possible to achieve nanocrystals with crystallographically defined surface facets and high surface area, which can be considered as ideal model catalysts for catalytic studies under realistic conditions. In this presentation, I will showcase how we can make use of ceria nanoshapes as both catalyst and catalyst support to gain molecular level understanding of the shape effect in catalysis through a combination of detailed in situ spectroscopic and kinetic studies. Insights have been gained into how the surface structure of ceria catalyst affects its redox and acid-base properties and those of ceria-supported catalyst.
It is suggested that the surface structure of ceria controls the catalytic performance through the structure-dependent surface sites geometry, lattice oxygen reactivity, surface vacancy formation energy, defect sites and coordinatively unsaturated sites on ceria. The study provides fundamental basis for both the improvement of current heterogeneous catalysts and the design of highly efficient catalyst via shape control without changing the catalyst composition.
Dr. Zili Wu is currently a research staff member with a joint appointment between Chemical Sciences Division and the Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee. He earned his PhD in Physical Chemistry in 2001 from the Dalian Institute of Chemical Physics, Dalian, China. From 2003-2006 Dr. Wu did his Postdoctoral Research in Chemistry at Northwestern University.
Dr. Wu is a member of several professional societies which include the American Chemical Society, North American Catalysis Society. He is a Journal reviewer for many journals including the Journal of American Chemical Society, Chemical Communications, Catalysis Communications, and the Journal of Catalysis.