Shining Light on Hydrogen: Solar-Powered Catalysis with Transition Metals.

Artificial photosynthesis offers a promising pathway to address environmental challenges and the global energy crisis by converting solar energy into storable chemical fuels such as hydrogen. Among various photocatalysts, transition metal-based materials have garnered significant attention due to their tunable crystal phase, morphology, surface active sites, and other key properties. This review provides a comprehensive overview of recent advances in transition metal-based photocatalysts for hydrogen production, with a particular focus on modification strategies and their underlying mechanisms. By systematically classifying these materials, this work highlights effective approaches for enhancing their catalytic performance, including structural engineering, electronic modulation, and interfacial optimization. Furthermore, this work discusses the fundamental principles governing these modifications, offering deeper insights into their roles in charge separation, surface reactions, and stability. Finally, this work outlines future research directions and key challenges in the rational design of highly efficient transition metal-based photocatalysts for sustainable hydrogen production.