Application of Carbon Supported Pt_core–Au_shell Nanoparticles in Methanol Electrooxidation

Abstract

Pt/C catalyst (carbon supported Pt nanoparticles) is synthesized through a microwave-assisted polyol process. Moreover, it is further employed as the starting material to prepare the Pt@Au/C catalyst (carbon supported Ptcore–Aushell nanoparticles) by a heteroepitaxial growth method using glucose as a reducing agent. The research results indicate that the slow reduction of the Au precursor caused by glucose successfully induces the Au atoms to grow around the Pt nanoparticles in the Pt/C catalyst to form the Au shell, whose structure transforms gradually from the Pt to Au fcc structure during the course of its growth. Moreover, the Au shell of the Ptcore–Aushell nanoparticles retains the Pt fcc structure when the theoretical atomic ratio between Au and Pt atoms (RAu/Pt) in the catalyst is less than 0.2. Furthermore, the Au shell with the Pt fcc structure in the Pt@Au/C catalysts (RAu/Pt ≤ 0.2) simultaneously bestows on the catalysts high methanol electrooxidation activity, excellent CO tolerance, and satisfactory performance for CO electrooxidation.