Photocorrosion, Protection, and Predictive Design in Solar Water Splitting

Photoelectrochemical (PEC) technology is a promising pathway for cost-effective, renewable, and clean fuel production from sunlight and water, addressing critical global energy demands. Despite extensive efforts, the major challenges, including unsatisfactory solar-to-hydrogen (STH) efficiency of less than 11.2% and limited long-term stability of less than 3000 h, for the commercialization of PEC water-splitting devices remain unresolved. To strengthen PEC performance and facilitate commercialization, we provide a comprehensive review of key fundamental mechanisms, recent advances in functional materials, interfacial engineering strategies, advanced characterization methods, and computational strategies. These aspects are interrelated and can synergistically form a feedback loop. In particular, computing strategies, which involve artificial intelligence (AI) for predicting device performance and automating experimental processes, can enable circulation within the feedback loop and hence accelerate the advancement of PEC water-splitting devices toward commercial viability (STH efficiency: >15% and long-term stability: >5 years). Ultimately, we aim to inspire researchers in this community through this comprehensive approach to the commercial production of green hydrogen applicable to diverse industrial sectors.