Low-loading cobalt coupled with nitrogen-doped porous graphene as excellent electrocatalyst for oxygen reduction reaction

Abstract

We developed a facile method to synthesize nanocomposites of cobalt loaded nitrogen doped graphene (Co–N-rGO), acting as a highly active non-precious metal catalyst for the oxygen reduction reaction (ORR). In alkaline media, the Co–N-rGO catalyst displayed a low overpotential, larger current density, better durability, and methanol tolerance ability toward ORR. Kinetic parameter analysis showed a high selectivity to an apparent four-electron transfer process on the Co–N-rGO catalyst for ORR with an average electron transfer number of 3.97. The excellent activity of the Co–N-rGO catalyst (0.44% Co) may result from its well-constructed porosity with high specific surface area and a synergistic effect between the N-rGO and cobalt oxide species.