Activation and Deactivation of Oxide-Supported Gold Catalysts for CO Oxidation prepared from an Organometallic Precursor: Characterization by Infrared and X-Ray Absorption Spectroscopies
نویسندگان
چکیده
Introduction Highly dispersed supported gold catalysts have attracted wide interest because of their high activities and selectivities for reactions including low-temperature oxidation of CO, even in the presence of H2. Notwithstanding extensive research on supported gold catalysts, fundamental questions remain, such as what are the catalytically active sites and reaction mechanisms. By using Au(CH3)2(acac) (acac is acetylacetonate) as a precursor and controlling the degree of aggregation of the gold on the support (MgO or CeO2), we have been able to investigate the genesis of a CO oxidation catalyst containing extremely small gold clusters resulting from activation by removal of methyl ligands from the supported gold complex.
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