Investigation of Heteroatom (N, P, S) Doping on the Oxygen Reduction Reaction Catalytic Activity of Graphene

The oxygen reduction reaction (ORR) at the cathode plays a key role in controlling the performance of fuel cell, and the efficient ORR electrocatalysts are essential for practical applications of the fuel cells. Currently, Pt-based electrocatalysts with the best performance are widely used in fuel cells, but Pt is very expensive. The introduction of various heteroatom (N, P, S) into graphene has a great effect on the ORR activity of samples prepared by thermal decomposition in this study. In order to understand the discrepant ORR activity of the doped graphene-based catalysts, electrochemical experiments and theoretical calculation were performed. According to the results and analysis, it is proposed that heteroatom doping alters the surface state of graphene materials. Different adsorption energy between O-2 molecule and heteroatom doped graphene are produced as a result, which alters the bond distance of O-2 molecule. The obtained results can be used for designing and developing new and suitable electrocatalysts for ORR in the future.