Recent advances in high-loading single-atom catalysts

Single-atom catalysts (SACs) have unique advantages over traditional nanoparticle-based catalysts. They are promising for various green energy technology applications. However, single atoms with high surface energy are prone to aggregation. Common SACs are often limited to low loadings of catalytically active sites, resulting in inadequate catalytic performance. In this context, high-loading SACs (HL-SACs) are much more desirable. The increased density of active sites also creates unique synergistic effects, bringing beneficial catalytic properties. This short review article summarizes recent advances in HL-SACS. We first review new synthesis methods to obtain HL-SACs. Then, we highlight studies discussing the effects of increased metal mass loadings on catalytic performances in terms of activity, selectivity, and stability. Last, we present our views on key research areas to move this field forward. We hope this review can drive the development of high-performance HL-SACs to realize their practical applications.