Methanol electro-oxidation on carbon-supported and Pt-modified Au nanoparticles

Methanol electro-oxidation on Pt-modified Au nanoparticles was studied in aqueous 0.5 M H₂SO₄/1 M CH₃OH. The Pt-modified Au nanoparticles showed lower values than pure Pt nanoparticles in area-specific current densities. The activity also decreased with lower amounts of Pt on the Pt-modified Au nanoparticles. This result indicates that the intrinsic activities of the Pt-modified Au nanoparticles were lower than that of Pt/C. This phenomenon may be due to the strengthened Pt–CO bonding or the weakened ensemble effect in the methanol electro-oxidation. However, in the Pt-specific current densities, the Pt-modified Au nanoparticles showed higher values than pure Pt nanoparticles. This enhanced electrocatalytic activity could be attributed to more reaction-favorable surface structures of Pt-modified Au nanoparticles, which most likely lead a high level of Pt utilization for the electro-oxidation reaction.