Chemical vapor deposition of gold on Al2O3, SiO2, and TiO2 for the oxidation of CO and of H2

Catalysis Letters (Impact Factor: 2.31). 03/1998; 51(1-2):53-58. DOI: 10.1023/A:1019020614336


In order to clarify the effect of metal oxide support on the catalytic activity of gold for CO oxidation, gold has been deposited on SiO2 with high dispersion by chemical vapor deposition (CVD) of an organo-gold complex. Comparison of Au/SiO2 with Au/Al2O3 and Au/TiO2, which were prepared by both CVD and liquid phase methods, showed that there were no appreciable differences in their catalytic activities as far as gold is deposited as nanoparticles with strong interaction. The perimeter interface around gold particles in contact with the metal oxide supports appears to be essential for the genesis of high catalytic activities at low temperatures.

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    • "However, the silica supported Au catalyst has little activity for CO oxidation. Several methods, such as chemical vapor deposition [13], chemical capture [14] and micelle deriving method [15], were proposed to increase the activity of Au catalysts, which are efficient but the preparations are inapposite for general application. "
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