Recent advances in single-atom catalysts (SACs) for photocatalytic applications

Artificial photocatalysis represents a hopeful avenue for tackling the global crisis of environmental and energy sustainability. The crux of industrial application in photocatalysis lies in efficient photocatalysts that can inhibit the recombination of photogenerated charge carriers, thereby boost the efficiency of chemical reactions. In the past decade, single-atom catalysts (SACs) have been growing extremely rapidly and have become the forefront of photocatalysis owing to their superior utilization of metal atoms and outstanding catalytic activity. In this work, we provide an overview of the latest advancements and challenges in SACs for photocatalysis, focusing on the photocatalytic mechanisms, encompassing the generation, separation, migration, and surface extraction of photogenerated carriers. We also explore the design, synthesis, and characterization of SACs and introduce the progress of SACs for photocatalytic applications, such as water splitting and CO₂ reduction. Lastly, we offer our personal perspectives on the opportunities and challenges of SACs in photocatalysis, aiming to provide insights into the future studies of SACs for photocatalytic applications.