Single Atom Catalysis
Supported metal catalysts are often most effectively utilized when the metal is dispersed as extremely small particles - and in the limit as isolated metal atoms. We explore synthetic approaches for creating supported single metal atoms, site specific techniques to characterize their existence and functionality, and approaches to tune their reactivity through metal-support interactions to enable unique catalytic behavior for selective catalysis.
The reaction environment in heterogeneous catalysis can include harsh, complex conditions, often inducing structural changes in the catalyst geometry and surface bound species. This restructuring commonly alters catalyst reactivity. We investigate this restructuring to understand how it affects catalyst performance and how it may be exploited for optimal reactivity and control over selectivity.
Metal nanostructures exhibit unique light-matter interactions enabling them to strongly concentration visible photons in small volumes at their surfaces. Coupled with their inherent catalytic capabilities, this provides unique opportunities for using solar energy to control catalytic processes. We are primarily interested in understanding when and how photons can be used to control the outcome of catalytic processes.
CO2 Conversion Chemistry
Ab-initio quantum chemical density functional theory (DFT) computational methods are utilized to develop molecular level insights into the mechanisms that control the performance and selectivity of metal catalysts in CO2 reduction by hydrogen. Of particular interest is uncovering descriptors that can be related to experimentally observed dependence of reaction selectivity on catalyst composition and structure.
Projects In Collaboration with Ian Wheeldon and Charlie Wyman
Processes that enable economically viable conversion of biomass into chemicals or fuels require high selectivity. We couple catalytic processes with unique raw biomass pretreatment or biological sugar conversion technologies to develop viable biomass conversion approaches. Our approaches exploit organosilane surface functionalization chemistry along with metal deposition to control catalytic selectivity via steric and electronic interactions and utilize homogeneous or heterogeneous acid sites.
Photocatalytic water splitting is one potential route for sustainably harvesting solar energy in the form of chemical bonds. We focus on understanding the fundamentals requisite for assembling these multi-component systems, which are conducive to high chemical reactivity.