Recent advances of single-atom alloy catalyst: Properties, synthetic methods and electrocatalytic applications

Developing high-performance and cost-effective electrocatalysts for clean and renewable energy conversion process has been proved a promising approach to deal with the global energy and environment issues. Single-atom alloy (SAA) catalyst, with foreign metal atoms atomically dispersed in the surface of a host metal, combines the merits of conventional metal alloys and single-atom catalysts. The maximum atomic utilization of active metal and unique structural and electrical properties of SAA offer great potential in boosting electrocatalytic activity and reducing the cost of manufacture. Meanwhile, the well-defined active sites raise an opportunity to shed the light on structure-activity relationship and further direct the synthesis of high-efficiency electrocatalysts. Herein, we focus on the recent developments of advanced SAA catalysts and discussed the general properties of SAAs. Then the design principle and synthetic methods were summarized. Next, we highlighted the practical applications of SAAs in electrocatalytic energy conversion and chemicals production, including hydrogen evolution reaction, oxygen evolution reaction, CO2 reduction reaction, N2 reduction reaction and other representative reactions. Finally, the challenges and future directions of SAAs are presented.