Atom-level interfacial synergy of single-atom site catalysts for electrocatalysis

Single-atom site catalysts(SACs) have made great achievements due to their nearly 100% atomic utilization and uniform active sites. Regulating the surrounding environment of active sites, including electron structure and coordination environment via atom-level interface regulation, to design and construct an advanced SACs is of great significance for boosting electrocatalytic reactions. In this review, we systemically summarized the fundamental understandings and intrinsic mechanisms of SACs for electrocatalytic applications based on the interface site regulations. We elaborated the several different regulation strategies of SACs to demonstrate their ascendancy in electrocatalytic applications. Firstly, the interfacial electronic interaction was presented to reveal the electron transfer behavior of active sites. Secondly, the different coordination structures of metal active center coordinated with two or three non-metal elements were also summarized. In addition, other atom-level interfaces of SACs, including metal atom–atom interface, metal atom-X-atom interface(X: non-metal element), metal atom-particle interface,were highlighted and the corresponding promoting effect towards electrocatalysis was disclosed.Finally, we outlooked the limitations, perspectives and challenges of SACs based on atomic interface regulation.