Amorphous Substrate-Supported Single-Atom Catalysts: Design Strategies, Electronic Regulation, and Catalytic Applications

Single-atom catalysts (SACs) represent a frontier in catalysis, yet their stability and activity are critically dependent on the choice of support material. Recently, amorphous materials have emerged as an ideal platform for hosting SACs, thanks to their long-range disordered structure that confers abundant defects, dangling bonds, and coordinatively unsaturated sites. These features not only effectively stabilize metal single atoms against aggregation but also facilitate precise electronic modulation of the active sites through robust metal–support interactions, thereby optimizing reaction pathways. This review systematically summarizes the design strategies, electronic regulation mechanisms, and cutting-edge applications of amorphous material-supported SACs (including amorphous carbon, carbon nitride, and metal oxides) in electrocatalysis (e.g., water splitting, nitrogen reduction) and photocatalysis (e.g., H₂ evolution, CO₂ reduction). Furthermore, it discusses the current challenges in precise synthesis, structural characterization, theoretical modeling, and practical implementation, while providing perspectives on future research directions. This work aims to offer novel insights for designing the next generation of high-performance SACs.