Recent advances in environmental applications, emerging synthesis methods and characterization techniques of single-atom catalysts

Single-atom catalysts (SACs) have been of great interest to researchers since their inception due to their high atomic utilization rates (up to 100 %), unique geometrical configurations, abundance of active sites, and excellent activity and selectivity in various catalytic reactions. Herein，we make an overview of the progress in SAC research in recent years, including a brief description of traditional synthesis and SAC characterization methods, highlighting new synthesis methods and the incorporation of density function theory (DFT) to guide catalyst development, analyzing current research bottlenecks, and looking ahead to the future of SAC research in terms of new development strategies and the application of new materials. In conclusion, our work provides some references for future SAC research work, especially on synthesis strategies and industrial applications.