Enhanced Oxygen Reduction Activity in Acid by Tin-Oxide Supported Au Nanoparticle Catalysts

Gold nanoparticles supported on hydrous tin-oxide are active for the four-electron oxygen reduction reaction in an acid electrolyte. The unique electrocatalytic of the Au–SnO is confirmed by the low amount of peroxide detected with rotating ring-disk electrode voltammetry and Koutecký-Levich analysis. In comparison, Au supported on Vulcan carbon and catalysts both produce significant peroxide in the acid electrolyte, indicating only a two-electron reduction reaction. Characterization of the catalyst reveals a high-surface area, amorphous support with gold metal particles. The high catalytic activity of the Au–SnO is attributed to metal support interactions. The results demonstrate a possible path to non-Pt catalysts for proton exchange membrane fuel cell cathodes.