INOR 365 |
| T. Don Tilley1, Andrew W. Holland2, Guangtao Li2, Chika Nozaki2, and Alexis T. Bell3. (1) Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720-1460, (2) Department of Chemistry, University of California, c/o Tilley Group, Berkeley, CA 94720, (3) Department of Chemical Engineering, University of California, Berkeley, Berkeley, CA 94720-1462 |
| We have developed a non-aqueous, molecular precursor approach to the preparation of mixed-element oxides, which allows molecular-level control over the chemical structure and nanostructure of the resulting materials. This approach, which we refer to as the thermolytic molecular precursor method, has been used to obtain highly dispersed mixed-element oxide materials. In some cases, this methodology provides heterogeneous catalysts that possess superior properties relative to catalysts with the same composition, but prepared by traditional aqueous methods. It has also been found that certain molecular precursors are useful for introduction of surface-attached catalytic species. For many heterogeneous catalysts, it is apparent that desirable properties are associated with well-defined active sites containing one or only a few metal centers on the surface of a support. Given the increasing interest in the structure and catalytic chemistry of supported iron centers, we have attempted to develop reliable routes to stable, well-defined inorganic iron species bound to a silica support. We have described a process for the introduction of isolated, tetrahedral iron(III) centers onto a silica surface, involving grafting reactions with molecular precursors. This method produces iron sites that are remarkably stable with respect to thermal degradation to iron oxide clusters. The resulting catalysts display good activities and selectivities for the oxidation of various hydrocarbons, using hydrogen peroxide as the oxidant. |
|
Homogeneous and Heterogeneous Oxidation Catalysis
8:30 AM-12:05 PM, Tuesday, August 24, 2004 Pennsylvania Convention Center -- 108A, Oral
Division of Inorganic Chemistry |