Ordered platinum–bismuth intermetallic clusters with Pt-skin for a highly efficient electrochemical ethanol oxidation reaction

Abstract

The ethanol oxidation reaction is extensively explored, but electrocatalysts that could achieve a complete oxidation pathway to CO₂/CO₃²⁻ are much less reported. Here, we synthesize a monatomic Pt layer (Pt-skin) on ordered intermetallic PtBi clusters (PtBi@Pt) supported on graphene via a single atom self-assembling (SAS) method to form a superior catalyst. The PtBi@Pt with an ultrafine size (∼2 nm) delivers an extremely high mass activity of 9.01 mA μg_Pt⁻¹, which is 8-fold more active than the commercial Pt/C; significantly, in situ Fourier transform infrared spectroscopy indicates that ethanol is completely oxidized to CO₃²⁻ on the PtBi@Pt, accompanied by 12 electron transfer, as is further demonstrated by the density functional theory results.