Generating charge carriers with lifetimes long enough to drive catalysis is a critical aspect for photoelectrochemical and photocatalytic systems, and a key determinant of their efficiency. Metal oxides are widely explored as photoanodes for photoelectrochemical water oxidation. However, their application is limited by the disparity between the picosecond–nanosecond lifetimes of electrons and holes photoexcited in bulk metal oxides versus the millisecond–second timescale of water oxidation catalysis. This Review addresses the charge-carrier dynamics underlying the performance of metal oxide photoanodes and their ability to drive photoelectrochemical water oxidation, alongside comparison with metal oxide function in photocatalytic and electrocatalytic systems. We assess the dominant kinetic processes determining photoanode performance, namely, charge generation, polaron formation and charge trapping, bulk and surface recombination, charge separation and extraction, and, finally, the kinetics of water oxidation catalysis. We examine approaches to enhance performance, including material selection, doping, nanostructuring, junction formation and/or co-catalyst deposition. Crucially, we examine how such performance enhancements can be understood from analyses of carrier dynamics and propose design guidelines for further material or device optimization.

产生寿命足以驱动催化的电荷载流子是光电化学和光催化系统的关键方面，也是其效率的关键决定因素。金属氧化物被广泛用作光电化学水氧化的光阳极。然而，它们的应用受到体金属氧化物中光激发电子和空穴的皮秒 - 纳秒寿命与水氧化催化的毫秒 - 秒时间尺度之间的差异的限制。本综述讨论了金属氧化物光阳极性能背后的电荷载流子动力学及其驱动光电化学水氧化的能力，并与光催化和电催化系统中的金属氧化物功能进行了比较。我们评估了决定光电阳极性能的主要动力学过程，即，电荷产生、极化子形成和电荷俘获、本体和表面复合、电荷分离和提取，最后是水氧化催化的动力学。我们研究了提高性能的方法，包括材料选择、掺杂、纳米结构、结形成和/或助催化剂沉积。至关重要的是，我们研究了如何通过载流子动力学分析来理解这种性能增强，并为进一步的材料或设备优化提出设计指南。