High Throughput\nScreening and Effective Optimization\nStrategy of WO<sub>3</sub>‑Supported Single-Atom Catalysts\nfor Electrocatalytic Nitrogen Reduction Reaction

As the main method of industrial ammonia synthesis, the\nHaber–Bosch\nprocess has high energy consumption and will cause serious pollution\nto the environment, electrochemical ammonia synthesis provides an\nideal strategy to solve this problem, however, the lack of highly\nactive and selective catalysts limits its industrial application.\nTo develop an efficient electrochemical nitrogen reduction (eNRR)\ncatalyst, we designed and screened 38 WO<sub>3</sub>-supported single-atom\ncatalysts (SACs) by density functional theory (DFT) calculations.\nBased on a four-step screening strategy, i.e., the stability of catalysts,\nnitrogen adsorption, catalytic activity, and selectivity, U/WO<sub>3</sub> was screened out to have a low limit potential of −0.48\nV when eNRR following the consecutive pathway. The electronic structure\nanalysis shows that the effective activation of nitrogen by U/WO<sub>3</sub> is due to the interaction that effectively moves the molecular\norbitals of nitrogen to the low-energy region. Furthermore, we found\nthe presence of oxygen vacancies on the WO<sub>3</sub> substrate can\neffectively enhance the stability and catalytic activity of U/WO<sub>3</sub> to NRR, in which the limiting potential of the distal path\nbecomes −0.35 V, but it also makes the desorption of NH<sub>3</sub> more difficult. This theoretical work provides a reasonable\nstrategy for designing efficient eNRR catalysts under ambient conditions.