Abstract

It is well known that bimetallic catalysts often show novel properties that are not present on either of the parent metal surfaces. However, it is difficult to know a priori how the chemical properties of a particular bimetallic surface will be modified relative to the parent metals. In the past few years our research group has investigated the novel catalytic properties of various bimetallic systems, using a combination of Density Functional Theory (DFT) modeling, surface science studies on single crystal surfaces, and reactor evaluations of supported bimetallic catalysts

In the current presentation we will use several probe reactions to demonstrate the unique chemical and catalytic properties of bimetallic systems. We will use the hydrogenation of alkenes, which is a reaction that requires relatively weak bonding of atomic hydrogen and alkenes, to demonstrate the utilization of bimetallic surfaces to enhance the hydrogenation activity; we will also use the selective hydrogenation of the C=O bond in unsaturated aldehydes to illustrate the possibility of controlling the selectivity with bimetallic surfaces. Next, we will present results for controlling the activity and selectivity of bimetallic surfaces for the reforming of oxygenates (alcohols and glycols), which is a reaction that requires relatively strong bonding of both hydrogen and oxygenates. Finally, we will present thermodynamic stability and kinetic measurements regarding the stability of bimetallic surfaces in the presence of oxygen and hydrogen. Overall, these results demonstrate the possibility of selecting catalytic materials with desirable activity, selectivity and stability based on the center of d-band of bimetallic surfaces, making it possible to predict bimetallic formations/structures with desirable chemical properties.

Biography

Jingguang Chen is the Claire D. LeClaire Professor of chemical engineering at the University of Delaware. He received his B.S. degree from Nanjing University and his Ph.D. degree from the University of Pittsburgh. He spent one year in Germany as a Humboldt Postdoctoral Fellow before starting his career at the Exxon Corporate Research Laboratories in 1989. In 1998 he accepted a faculty position at the University of Delaware and served as the Director of the Center for Catalytic Science and Technology (CCST) from 2000 - 2007. He has over 170 journal publications and 17 US patents. He is very active in serving the surface science and catalysis communities, including responsibilities as the Chair for the Gordon Research Conference on Catalysis in 2002, the Chair of the Philadelphia Catalysis Club in 2004, the Board of Directors for the North American Catalysis Society, and the Catalysis Secretariat of the American Chemical Society. He has won many awards, including the recent Excellence in Catalysis Award from the New York Catalysis Society.