Janus MoPC Monolayer with Superior Electrocatalytic Performance for the Hydrogen Evolution Reaction
Huan Lou, Guangtao Yu, Meng Tang, Wei Chen, Guochun Yang
Abstract
Designing the earth’s abundant and high-performance electrocatalysts, which possess high stability, excellent electrical conductivity, inherent active sites, and catalytic activity identical with Pt, is challenging but crucial for the hydrogen evolution reaction (HER). By first-principles structure search simulations, we identify a new two-dimensional (2D) MoPC material with the Janus structure as a promising catalyst. This novel 2D monolayer has superior stability and metallic conductivity. Especially, it exhibits a remarkable HER catalytic activity, where all of the constituent atoms, including Mo, P, and C, can uniformly act as active sites in view of the near-zero ΔGH* value. Its active site density counts up to 1.46 × 1015 site/cm2, larger than that of many reported materials and even comparable to Pt. The excellent HER catalytic activity can also be maintained at a very high H coverage with or without external strain. The MoPC monolayer can produce H2 spontaneously through the favorable Volmer–Heyrovsky pathway. The detailed catalytic mechanism behind the high HER activity has been also analyzed. Our work provides a feasible action for the experimental synthesis of excellent HER catalysts.