Active Site Identification and Interfacial Design of a MoP/N-Doped Carbon Catalyst for Efficient Hydrogen Evolution Reaction

Systematic research on potential active sites, in particular, the intrinsic mechanism between the nitrogen-doped carbon (NC) and transition metal phosphides (TMPs) is of great significance to boost the development of hydrogen evolution reaction (HER) catalysts. In this work, we designed a reliable scheme to verify the interaction of a molybdenum phosphide/NC (MoP/NC) catalyst derived from theoretical calculations. According to our screening calculations of 19 feasible active sites on MoP/NC, interface engineering of MoP/NC was proved to provide an electronic transfer from the Mo layer to the graphene layer, thereby activating N-doped graphene serve as active sites. Furthermore, the sp2 or sp3 H-adsorption patterns could effectively adjust the adsorption strength, which promotes the HER catalytic activity. Meanwhile, to confirm the calculated results, an ultrathin N-doped carbon-coated MoP globular material (MoP/NC) was constructed, whose catalytic performance greatly surpasses that of the MoP material in both acid and alkaline media. These findings deepen the understanding of the intrinsic mechanism of functional carbon-incorporated TMPs and provide scientific guidance for the interface design of an efficient HER electrocatalyst.