Solar-Driven Hydrogen Production: Recent Advances, Challenges, and Future Perspectives

Solar H2 production is considered as a potentially promising way to utilizesolar energy and tackle climate change stemming from the combustion of fossil fuels.Photocatalytic, photoelectrochemical, photovoltaic−electrochemical, solar thermochem-ical, photothermal catalytic, and photobiological technologies are the most intensivelystudied routes for solar H2 production. In this Focus Review, we provide a comprehensivereview of these technologies. After a brief introduction of the principles and mechanisms ofthese technologies, the recent achievements in solar H2 production are summarized, with aparticular focus on the high solar-to-H 2 (STH) conversion efficiency achieved by eachroute. We then comparatively analyze and evaluate these technologies based on the metricsof STH efficiency, durability, economic viability, and environmental sustainability, aimingto assess the commercial feasibility of these solar technologies compared with currentindustrial H 2 production processes. Finally, the challenges and prospects of future researchon solar H2 production technologies are presented.