Recent Research Progresses and Challenges for Practical Application of Large-Scale Solar Hydrogen Production

Solar hydrogen production is a promising pathway for sustainable CO₂-free hydrogen production. It is mainly classified into three systems: photovoltaic electrolysis (PV-EC), photoelectrochemical (PEC) system, and particulate photocatalytic (PC) system. However, it still has trouble in commercialization due to the limitation of performance and economic feasibility in the large-scale system. In this review, the challenges of each large-scale system are, respectively, summarized. Based on this summary, recent approaches to solving these challenges are introduced, focusing on core components, fabrication processes, and systematic designs. In addition, several demonstrations of large-scale systems under outdoor conditions and performances of upscaled systems are introduced to understand the current technical level of solar-driven hydrogen production systems for commercialization. Finally, the future outlooks and perspectives on the practical application of large-scale solar-driven hydrogen production are discussed.