Tuning the Hydrogen Evolution Reaction Activity of MoC-Supported Graphene Using Defect and N-doping

The hydrogen evolution reaction (HER) of MoC-supported graphene is studied using density functional theory in conjunction with a thermodynamic approach and a kinetic model for the exchange current density. We verify that MoC (001) is one of the most stable surface terminations at standard conditions and can be strongly coupled with graphene. Our main finding is that the MoC-supported graphene heterostructure has an optimal HER activity that can be tuned through the interplay of nitrogen dopants and defects on graphene. We further determine the overpotential, rate limiting step, and minimum reaction pathways for HER mechanism in acidic environment.