Enhanced Catalytic Activity of Bimetallic Ordered Catalysts for Nitrogen Reduction Reaction by Perturbation of Scaling Relations

It remains a challenge to explore a catalyst that can address the activity and selectivity of the electrochemical nitrogen reduction reaction (NRR). One of the key points is finding the means to go beyond the limitations imposed by linear scaling relations (LSRs). Intermetallic compounds (IMCs) that have a uniform active site structure with controlled atomic ensemble size and electronic structure can be used to design catalysts with excellent performance. In this study, we calculate the adsorption behavior of 11 nitrogen reduction intermediates on (111) surfaces of 29 L12 IMCs. The ensemble size of the active sites can affect the adsorption configuration and activity of the intermediates through geometric and electronic effects and, more importantly, perturb the LSRs. Allowing NNH to take a more stable tilted adsorption configuration on the heterometal hollow site (e.g., the "MoRuRu" hollow site) and increasing the adsorption strength of NH2 on single atom sites (e.g., the isolated Mo or Ta atom on the Pd3Mo or Cu3Ta surface, respectively) via the covalent effect are essential instruments to go beyond the LSRs in constructing efficient catalysts. Pd3Mo is proposed as an idealist catalyst among thes IMCs we calculated, with a low limiting potential of -0.31 V and the ability to suppress the competing hydrogen reduction reaction (HER). The present study demonstrates the potential of IMCs to transcend LSRs and serve as excellent NRR catalysts.