Modification of Ag nanoparticles/reduced graphene oxide nanocomposites with a small amount of Au for glycerol oxidation

摘要

The surface modification of Ag nanoparticles supported on reduced graphene oxide (RGO) with a small amount of Au and the activity of Au-modified Ag/RGO (Au-Ag/RGO) catalysts for the electrooxidation of glycerol have been investigated. The deposition of Au on Ag/RGO nanocomposites was performed electrochemically, and the Au-Ag/RGO catalysts with Au:Ag atomic ratios in a range from 1:303 to 1:43 were prepared. The characterization of catalysts reveals a partial coverage of the Ag nanoparticle surface by Au adatoms. Cyclic voltammetric measurements indicate that the Au-Ag/RGO catalysts show almost the same activity as Au/RGO in terms of the geometric surface area of glassy carbon substrates for glycerol oxidation in alkaline solution, while Ag/RGO shows no catalytic activity. The Au Ag/RGO catalysts have great advantages over Au/RGO in terms of the Au mass specific activity. A significant improvement in the catalytic activity of Ag/RGO by the deposition of a small amount of Au and a high utilization of Au are achieved, and the result is of significance for preparing highly active catalysts at low cost by using less expensive metal and active metal. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.