CBE Seminar - William Schneider

Professor, Department of Chemical and Biomolecular Engineering, Concurrent Professor, Department of Chemistry and Biochemistry, Notre Dame

The Dynamic Nature of the Catalyst “Active Site”

Dr. William F. Schneider

Professor

Department of Chemical and Biomolecular Engineering

Concurrent Professor, Department of Chemistry and Biochemistry

University of Notre Dame

 

Abstract
Catalysis touches our lives every day, from creating the products we use, the fuels we power our lives with, to cleaning up undesirable wastes. Catalysis can even make the headlines, as with the recent case of Volkswagen and the failure of its vehicles to meet NOx emissions standards. Despite the pervasiveness of catalysis, advances are often incremental and discoveries serendipitous, because the underlying molecular mechanisms and controlling factors under practical conditions are difficult to infer and even more difficult to control.

 

In this presentation I discuss these ideas in the context of the selective catalytic reduction (SCR) of NOx by Cu-exchanged zeolites, the NOx control strategy Volkswagen decided not to implement. These catalytic materials are both macroscopically and microscopically heterogeneous, and that microscopic heterogeneity has frustrated efforts to understand catalytic mechanism.  We employ first-principles density functional theory (DFT) coupled with molecular dynamics and advanced sampling techniques to unravel the microscopic distribution of sites within a material as a function of preparation conditions, the evolution of those sites under various environmental conditions, and the implications of these two on catalytic mechanism.  These models explain a wealth of experimental data and demonstrate the potential of modern simulation to tools to disentangle the complexities of a functioning catalyst.

 

Bio
Bill Schneider's expertise is in chemical and engineering applications of density functional theory (DFT).  After receiving his Ph.D. from the Ohio State University in 1991, he began his professional career in the Ford Motor Company Research Laboratory working on a variety of problems related to the environmental impacts of automobile emissions. There he developed an interest in the catalytic chemistry of NOx for diesel emissions control, and he has published extensively on the chemistry and mechanisms of NOx decomposition, selective catalytic reduction, trapping, and oxidation catalysis. In 2004 he joined the Chemical and Biomolecular Engineering faculty at the University of Notre Dame as an Associate Professor.  At Notre Dame he has continued his research into the theory and molecular simulation of heterogeneous catalysis, with particular emphasis on reaction environment effects on catalytic materials and their implications for mechanism and reactivity. He was promoted to Professor in 2010 and was recently recognized as a Fellow of the American Association for the Advancement of Science. He has co-authored more than 140 papers and book chapters and is a Senior Editor of the Journal of Physical Chemistry. He makes his home in Granger, Indiana with his three children, Justin, MiMi, and Meredith.