Anchoring Au Nanoparticles onto ZnO Nanowires by Heteroepitaxy

Supported Au nanoparticles (NPs) with sizes < 5 nm have been proved to be highly active for many important catalytic reactions [1]. The development of thermally stable supported Au NP catalysts, however, is challenging. Unlike other noble metals, Au NPs or clusters sinter rapidly during catalytic reactions at elevated temperatures or even under long-term storage [2]. There are many approaches to stabilizing supported metal NPs or clusters [3]. Our approach to developing sintering-resistant supported metal nanocatalysts is to anchor the active metal NPs to well-defined support surfaces by heteroepitaxial growth. We report here the synthesis of stable Au/ZnO nanostructured catalysts by epitaxially growing Au NPs onto the flat and clean surfaces of ZnO nanowires (NWs), the detailed atomic scale characterization of the fabricated catalysts, and their stability during the CO oxidation reaction.