The Department of Chemical Engineering and Materials Science at the University of California, Davis has a strong experimental program in catalysis and materials research emphasizing fundamental investigations motivated by technologically important problems and close interactions with industry. The research directed by Professor B. C. Gates involves catalyst preparation, characterization by physical methods, and testing in low- and high-pressure reactors.
Catalysis by structurally simple supported metal complexes and metal clusters
Organometallic precursors are used to prepare structurally simple metal oxide-supported metals, including single-metal-atom complexes, metal carbonyl clusters, and metal clusters. Examples include Os3, Ir4, and Ir6 clusters on MgO. The work is leading to fundamental understanding of the structure of the metal-support interface, the structures of metal clusters on supports, and the dependence of catalytic properties on cluster size and structure. Catalysts are tested with techniques including IR, EXAFS, EPR, and NMR spectroscopies, atomic-resolution STEM, GC, MS and others.
We are using ship-in-a-bottle syntheses as well as more conventional preparations to synthesize metal complexes and metal clusters in zeolite channels and cages, investigating their migration and conversion in reactive atmospheres. The materials include structurally simple catalysts (e.g., Rh1, Ir6 in HY zeolite). This research is collaborative with researchers at Chevron.
Metal oxide surface structure
Metal oxides are prepared to contain predominantly single surface species. Organometallic precursors are used to prepare structurally uniform catalytic sites at these locations. This work is leading to an understanding of how to control support surfaces to influence the catalytic properties.
Novel supported bimetallic catalysts
We are using organometallic precursors to prepare highly dispersed supported bimetallic catalysts which are used in simple catalytic test reactions. Examples include Rh-Ir and Os-Rh catalysts supported on MgO and on zeolites.
We are working with theorists at the University of Alabama (the group of David Dixon) to use density functional theory to characterize metal complexes and metal clusters on zeolites and oxide supports.
Reactions of lignin-derived compounds
Biomass conversion processes produce bio-oils that contain hundreds of compounds. In collaboration with Prof. David Block, we are developing reaction networks to understand the complex chemistry of lignin-derived compounds in reactions catalyzed by solids such as alumina-supported platinum in low- and high-pressure flow reactors. Previous work has focused on single-component feeds with reactants such as guaiacol, anisole, and cyclohexanone.