Computational screening of highly selective and active electrocatalytic nitrogen reduction on single-atom-embedded...

Billowy interest during nitrogen reduction reaction (NRR) for single-atom catalysts (SACs) has been evoked by the discovery of single transition metal (TM) atom structures featured by TM-N_x coordinate sites as an excellent catalytic center. However, a great challenge of currently available SACs, far away from industrial requirement, is the low activity and poor selectivity. Therefore, in NRR, the first-principles high-throughput screening calculations were performed to evaluate the feasibility of a single TM atom (from Sc to Au) embedded an artificial holey defective SnN₃ (d-SnN₃) monolayer. Here, all TM atoms can be stably anchored on d-SnN₃ (TM/d-SnN₃), meanwhile, most of adsorbed N₂ molecules can be favorably activated via the "σ donation - π* back-donation" interaction. Eventually, among 27 TM centers, V, Mo, Hf and Ta/d-SnN₃ stand out because of extremely low limiting potential (-0.21, -0.40, -0.56 and -0.54 V, respectively), lower than majority of TM-based NRR catalysts and far below that of the Ru (0001) surface (0.98 V), indicative of fast kinetics and low energy cost of NRR. Moreover, their intrinsic characteristic, such as centralized spin-polarization on these TM atoms, high-efficient prohibition of the competitive hydrogen evolution reaction is responsible for high selectivity with theoretical faradic efficiency of 100%. Also, multiple-level descriptors including ΔG_∗N, ICOHP, and Φ were used to make the source of NRR activity clear, realizing an efficient and quick prescreening among different candidates. Particularly, their excellent durability, kinetic stability and synthetic accessibility guarantee the feasibility in real experimental conditions.