Computational Design of Transition Metal Single-Atom Electrocatalysts on PtS₂ for Efficient Nitrogen Reduction

Electrocatalytic nitrogen reduction is promising to serve as a sustainable and environmentally friendly strategy to achieve ammonia production. Single-atom catalysts (SACs) hold great promise to convert N₂ into NH₃ because of the unique molecular catalysis property and ultrahigh atomic utilization ratio. Here, we demonstrate a universal computational design principle to assess the N₂ reduction reaction (NRR) performance of SACs anchored on a monolayer PtS₂ substrate (SACs-PtS₂). Our density functional theory simulations unveil that the barriers of the NRR limiting potential step on different SAC centers are observed to be linearly correlated to the integral of unoccupied d states (UDSs) of SACs. As a result, the Ru SAC-PtS₂ catalyst with the largest number of UDSs exhibits a much lower barrier of the limiting step than those of other SACs-PtS₂ catalysts and the Ru(0001) benchmark. Our work bridges the apparent NRR activity and intrinsic electronic structure of SAC centers and offers effective guidance to screen and design efficient SACs for the electrochemical NRR process.