Unveiling the HER and ORR activity origin of isolated Co sites supported on N-doped carbon

Electrocatalysis plays very important role in clean energy conversion. In which, developing high active and robust electrocatalysts for the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) are highly crucial and challenging. Using density functional theory (DFT) calculations, the Gibbs free energy diagrams and electronic structure of N-graphene, Ir-N4 and Co-N4 are investigated in this work. The results show that Co-N4 have the appropriate H adsorption and lower ORR overpotentials, which gives expectation of high multifunctional electrocatalytic performance. This theoretical study provides vital insights into the enhanced electrocatalytic mechanism of Co sites supported on N-doped carbon.