Non-carbon-supported single-atom site catalysts for electrocatalysis

Abstract

Single-atom site catalysts (SACs) have received considerable attention for electrocatalytic applications, owing to their maximum atom-utilization efficiency, well-identified active centers, and tunable supports. Carbon-supported SACs have been widely applied in electrocatalysis, and their progress has been intensively reviewed. Non-carbon-supported SACs have drawn ever-increasing attention recently, and are emerging as an indispensable class of SACs. This review comprehensively summarizes the recent exciting progress on the non-carbon-supported SACs and their applications in electrocatalytic reactions. Eight types of non-carbon-supported SACs are firstly categorized to show their diversity. Subsequently, the anchoring and stabilization mechanisms for each type of non-carbon-supported SACs are systematically unraveled. Furthermore, the advanced characterization techniques for identifying and monitoring the atomic structure of SACs are highlighted. Thereafter, the advances of non-carbon-supported SACs for electrochemical energy conversion are discussed, which emphasizes their applications in the hydrogen evolution reaction, the oxygen evolution reaction, the oxygen reduction reaction, the N₂ reduction reaction, and the CO₂ reduction reaction. Finally, perspective insights into the current challenges and the future prospects for non-carbon-supported SACs are provided.