Enhanced Methanol Oxidation in Acid Media on Pt/S, P Co-doped Graphene with 3D Porous Network Structure Engineering

A sulfur and phosphorous co-doped three-dimensional graphene (3D-SPG)-supported Pt nanoparticle (Pt/3D-SPG) catalyst with a unique 3D porous network structure was synthesized and employed as an efficient, environmentally friendly and robust catalyst for the methanol oxidation reaction (MOR). The unique 3D porous network structure of 3D-SPG is in favor of uniformly supporting Pt nanoparticles with an average size of 2.09 nm as well as enhancement of the mass transport of reactants and products. Hence, the Pt/3D-SPG catalyst shows improved stability, an electrochemical surface area over 15.5 and 30.8 % larger, and MOR performance of 1.6 and 2.2 times higher than S and P co-doped and P-doped graphene-supported Pt nanoparticle (Pt/SPG and Pt/PG) catalysts, respectively. The enhanced CO tolerance of the Pt/3D-SPG catalyst may result from the 3D porous network structure, which was not only favorable to release CO efficiently from the metallic Pt surface, but also could concentrate many more hydroxyl groups for enhancing CO _ads oxidation. The Pt/3D-SPG catalyst offer a unique strategy for designing and preparing 3D graphene-based catalysts, taking into account of the advantages of doping with different heteroatoms.