Solar water splitting for hydrogen generation over semiconductor photoelectrodes is a promising solution to the energy crisis and environmental issues. Because complex physical, chemical, and electrical processes are involved in solar energy conversion reactions, understanding the mechanisms is of great significance for the rational design of highly efficient solar water-splitting cells. This review describes the current mechanistic understanding of the adsorption of reactants, injection of charge carriers, and desorption of products during surface redox reactions. Variations of interfacial band-gap structures, the status of surface bonding, and the behavior of charge carriers in semiconductor photoelectrodes are discussed. This review could inspire further innovative work on understanding the mechanisms of solar water splitting.

太阳能水分解以通过半导体光电极产生氢是解决能源危机和环境问题的有希望的解决方案。由于太阳能转化反应涉及复杂的物理，化学和电气过程，因此了解其机理对于合理设计高效太阳能水分解池具有重要意义。这篇综述描述了在表面氧化还原反应过程中对反应物吸附，电荷载流子注入和产物解吸的当前机理理解。讨论了界面带隙结构的变化，表面键合的状态以及半导体光电极中电荷载流子的行为。这项审查可以激发关于理解太阳能水分解机理的进一步创新工作。