Coordination structures design of single-atom catalysts for enhanced hydrogen evolution reaction

The production of green hydrogen via water electrolysis represents a critical strategy for addressing future energy crises. However, the hydrogen evolution reaction (HER) at the cathode presents inherent activity limitations. Single-atom catalysts (SACs) have garnered significant attention as a promising solution due to their low cost, considerable catalytic activity, and high metal atom utilization. This review provides a comprehensive overview of recent advancements in SACs for HER, with a particular focus on the design of coordination structures. The recent advancements in the field from the perspectives of noble and non-noble metal SACs were reviewed firstly. Then the coordination structure regulation strategies with symmetric and asymmetric configurations of SACs for enhancing HER were summarized and the key design principles was proposed. Finally, the prospects and challenges in this area were further discussed. This review can provide reference for the rational design of high-performance HER catalysts. Single-atom catalysts (SACs) represent an advanced choice for catalyzing the hydrogen at the cathode during water electrolysis. Regulating the coordination structure offers a flexible and effective approach for performance enhancement. In this review, we present new insights into the design of coordination structures of nitrogen-doped carbon-based SACs for enhancing HER. • The recent advancements of noble and non-noble metal SACs for HER were reviewed. • The coordination structure regulation strategies of SACs were summarized. • The key design principles for enhancing HER were proposed. • The prospects and challenges of SACs for HER were discussed.