Single-atomic site catalysts for electrochemical nitrogen fixation

Renewable-energy-derived electrochemical nitrogen fixation represents a sustainable way to produce green ammonia (NH3), but the energy efficiency is limited by its sluggish kinetics and complex reaction pathways. Highly active, selective and robust electrocatalysts are strongly needed to promote the efficiency of nitrogen conversion. Here, we provide an overview of the recent progress in understanding the structure–function correlation of single-atomic site catalysts (SASCs) for electrochemical nitrogen fixation, to provide mechanistic insights and guide the future rational design of SASCs. First, we review the fundamental understanding of both N2 and oxynitride reduction on SASCs, with different hydrogenation pathways. Afterwards, we present the recent progress in the development of well-defined SASCs with various metal centres and the influence from local chemical environments, such as the coordination number, first-shell and second-sphere coordination. At last, we listed some perspectives on future study in this emerging research field. GRAPHICAL ABSTRACT IMPACT STATEMENT The paper provides mechanistic insights into the single-atomic site catalysts towards electrochemical nitrogen fixation.