Department of Chemical Engineering
3112 Ghausi Hall
University of California
Davis, CA 95616
Email: bcgates at ucdavis.edu
Website: Gates’ Catalysis Research Group
Our program in catalysis research emphasizes fundamental investigations motivated by technologically important problems and close interactions with industry. The research involves catalyst preparation, characterization by physical methods, and testing in low- and high-pressure reactors.
Catalysis by structurally simple supported 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 rhenium subcarbonyls on MgO and Ir4, Ir6, and Pt15 clusters on Alumina and in zeolites. 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 and the structure of the metal-support interface.
Solid superacid catalysts
Solid superacids are being investigated that have activities for butane isomerization even at room temperature. These catalysts may provide the first practical routes to low-temperature paraffin isomerization for clean-burning gasoline.
We are using ship-in-a-bottle syntheses as well as more conventional preparations to synthesize metal carbonyl clusters and metal clusters in zeolite cages. The materials include structurally simple catalysts (e.g., Ir4 in NaY zeolite) and very small metal clusters in zeolite L. We have been able to interconvert metal carbonyls such as and metal clusters such as Ir6. Our group has also investigated acidic zeolites such as HZSM-5 as paraffin conversion catalysts.
Novel supported bimetallic catalysts
We are using organometallic precursors to prepare highly dispersed supported metal catalysts, including bimetallics. Examples include Pt-Mo catalysts supported on alumina, where the close proximity of the two metals may confer favorable properties on auto exhaust conversion catalysts.
Catalyst preparation by sol-gel methods
The sol-gel technique gives precise control of the physical properties of amorphous metal oxides, but it has still found little application in catalyst preparation. We are investigating the effects of preparation variables on catalyst support properties made with organometallic precursors and using the method to prepare novel supported metal catalysts.
Experiments with powder and single-crystal samples
Understanding of the properties of supported metal catalysts requires precise characterization of the structure, including the structure of the metal-support interface. Such understanding is emerging from characterizations of metals supported on single crystals of metal oxides with techniques including IR, EXAFS, NMR and other physical techniques.