Professor, Chemical Engineering
Molecular modeling, computational heterogeneous catalysis, kinetics of complex reaction systems.
Our research program is focused on modeling the atomic features and molecular phenomena that govern catalysis and materials processing. We are using computational chemistry and molecular reaction modeling to examine the properties and performance for a wide range of different material including metals, bimetallics, metal oxides and zeolites for their use as heterogeneous catalysis, catalytic electrodes for fuel cells, and magnetic materials for memory device fabrication. The performance of these materials depends on their atomic surface structure and composition. The chemistry and kinetics at a solid-fluid interface are controlled by chemical bonding between the adsorbates and the surface as well as the environment at the active site.
We are developing a suite of tools that enable us to understand adsorbate-surface interactions and quantify the energetics of elementary reaction steps. This information is used to simulate the vast array of competing elementary surface steps, follow the temporal surface structure, and model material performance. We are therefore able to tie tunable atomic structural and compositional levers to the overall process chemistry or device performance. This provides a framework whereby we can begin to manipulate the atomic scale features (defect sites, alloys, supports solvents) toward the design of new materials. The computational tools that we are using/developing range from ab initio density functional theory and ab initio molecular dynamics methods to calculate the detailed electronic structure to first-principles based kinetic Monte Carlo simulation in order to follow the reaction kinetics.
We are currently examining a number of industrially relevant catalytic chemistries including the selective hydrogenation of oxygenates, the selective hydrogenation of alkynes, vinyl acetate synthesis, Fischer-Tropsch synthesis, methanol fuel cells, lean burn NOx reduction, oxychlorination of olefins, amination of alcohols, and olefin epoxidation. In addition, we are also looking at the processing of giant magnetoresistant materials for memory fabrication.