Catalysis by gold: New insights into the support effect

The metal-support interaction (MSI) plays an essential role in the catalysis by gold. We summarized the support effect on the catalysis by gold in this review. According to the reducibility of the oxide supports, we divide the supports into two categories: reducible metal-oxide (RMO) and irreducible oxide (IRO) supports. The catalytic mechanisms for low-temperature CO oxidation over RMO supported gold catalysts are discussed based on the recent progress on this topic and the key role of gold-support interface in the catalytic reactions is highlighted. To prolong the perimeters of the gold-support interfaces, one can both decrease the sizes of gold nanoparticles (GNPs) and tune the morphology of the support (e.g., shape, size, etc.). From the point of view of decreasing the size of both gold and the support simultaneously for maximizing the boundary of gold and the support, we classify the gold-based bimetallic catalysts into metal supported gold and inversely metal/RMO supported gold. The nanoporous gold (NPG) synthesized by dealloying bulk Au-Ag alloy can also be considered as an inversely Ag/AgOx supported gold catalyst. Thus, the traditional concept of support can be extended greatly. Finally, the strong metal-support interaction (SMSI) in the Au-based and Pt-based system has been compared to show the distinctive feature of gold catalysts. (c) 2013 Elsevier Ltd. All rights reserved