Oriented design of triple atom catalysts for electrocatalytic nitrogen reduction with the genetic-algorithm-based global optimization method driven by first principles calculations

Abstract

To rationally locate the high-performance atomically dispersed catalyst remains a challenge, despite wide explorations in numerous critical chemical reactions. Here, taking the cohesive-energy property of metals (E_c) as the descriptor, we systematically established the activity/selectivity/stability trends of the single- (SASs), double- (DASs) and triple-atom structures (TASs) for the electrochemical nitrogen reduction reaction (NRR). The results show that the TAS exhibits overall superior NRR performance compared with others, revealing its essential structural superiority. The origin of the superior activity of TASs can be traced to the weakened adsorption strength of the key intermediate NH₂ that significantly activates the rate-limiting step of *NH₂ hydrogenation. More importantly, we computationally explore 736 TAS catalysts via the on-the-fly oriented design driven by the genetic-algorithm-based global optimization method, and 146 candidates are extracted to enable the NRR and recommended for experimental synthesis. By counting up these promising TASs, one general rule, i.e., early transition metal atoms combining with late ones, was identified to design the feasible composition pattern of TASs for the NRR. This work deepens the fundamental understanding of the dependence of structural units on the catalytic ability of atomically dispersed metal catalysts, and large-scale triple atom material exploration may accelerate their practical application for the NRR or other systems.