论文信息 - Fine Structure of Novel Gold Catalysts Prepared by Coprecipitation

Fine Structure of Novel Gold Catalysts Prepared by Coprecipitation

Abstract Highly dispersed gold catalysts have been prepared by calcining the coprecipitates obtained from an aqueous solution of HAuCl4 and the nitrate of Fe, Co, Ni, or Be. They are active for the oxidation of CO even at such a low temperature as–70°C and become more active in the presence of moisture. The gold particles are hemispherical in shape and are nearly homodispersed with a mean diameter smaller than 10nm. Most of them are strongly attached at their flat planes to the metal oxide support exhibiting a specific crystal orientation. The chemical shifts in XPS showed that the ultrafine gold particles were electron deficient. The results of EXAFS studies suggested the possibility of the existence of gold atoms coordinated with iron atoms.

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