Thermal treated 3D graphene as a highly efficient metal-free electrocatalyst toward oxygen reduction reaction. (23rd November 2017) - Zhang, Lian Ying
Abstract: Thermal treated 3D graphene materials are developed as a highly efficient metal-free electrocatalyst toward oxygen reduction reaction (ORR). Electrochemical analysis reveals that the as-prepared sample shows comparable catalytic activity, better tolerance to methanol crossover effect as well as higher stability than those of commercial Pt/C. For the first time, we find that CO bonds on 3D graphene display a vital role in catalytic kinetics toward ORR, of which the CO bonds might influence the adsorption type between oxygen molecule and catalytic active sites on graphene surface. Meanwhile, the unique porous structure of 3D graphene materials are able to trap oxygen molecules, contributing to decrease in diffusion resistance while enhance electrolyte-electrode accessibility for fast mass transport. This work offers a highly efficient metal-free ORR catalyst obtained by a universal approach, and the prepared 3D graphene materials could be further utilized in other energy conversion/storage fields. Highlights: Thermal treated 3D graphene is developed as great metal-free catalyst for ORR. CO bonds on 3D graphene display a vital role in catalytic kinetics toward ORR. Thermal treated 3D graphene shows high catalytic activity and stability for ORR. Thermal treated 3D graphene could be obtained by a universal approach.