Fabrication of Gold Nanoprism Thin Films and Their Applications in Designing High Activity Electrocatalysts

A simple, one-step wet chemical method was developed for fabrication of closely packed gold nanoprism thin films (Au-PFs for short) on the indium tin oxide (ITO) coated glass substrates. Most Au prisms have micrometer-scale edge length and nanometer-scale thickness (herein defined as nanoprism according to the thickness). They are single crystalline, whose basal surfaces are atomically flat {111} planes and lateral surfaces are {110} planes. The Au-PFs were further used as the substrate electrodes to construct bimetallic and trimetallic Au-based catalysts. A tiny amount of Pt or Pd, the equivalent of a monolayer, was deposited onto the Au nanoprism thin film electrodes (Au-PFEs for short) by the underpotential deposition (UPD) of a Cu atomic layer on the Au surfaces, followed by redox replacement of the UPD Cu with a Pt or Pd monolayer. Interestingly, once after surface modification with a Pt monolayer, Au-PFEs exhibited greatly enhanced catalytic activity toward the electrooxidation of methanol and much better poison resistance than commercial Pt-based catalysts. The as-prepared bimetallic Au−Pt and trimetallic Au−Pd−Pt catalysts are expected to act as the promising electrocatalysts for the methanol oxidation.