Deposition of gold nanoparticles on carbons for aerobic glucose oxidation

Carbon materials such as activated carbon and carbon black have long been used as adsorbents, electrodes, and supports for metal catalysts. However, no attempt has yet been reported to deposit Au as small nanoparticles (NPs) on these carbon materials directly from Au precursor compounds. Until now, the most effective way to support Au NPs on activated carbon was to physically mix a carbon support with Au colloids prepared beforehand. Here we report that Au could be deposited as NPs on carbon materials directly from gold precursor compounds by deposition reduction method and by solid grinding method. In particular, the solid grinding of carbons with dimethyl Au(III) acetylacetonate, which has a certain degree of vapor pressure at room temperature, is a simple technique but surprisingly effective to deposit Au NPs with a mean diameter as small as 1.9 nm. These highly dispersed Au NPs on carbon supports were tested for glucose oxidation in water with molecular oxygen. A Au/nanoporous carbon (NPC) catalyst which exhibited relatively high catalytic activity has been kinetically studied for comparison with Au/metal oxides catalysts. (C) 2009 Elsevier B.V. All rights reserved.