Interface Engineering for Modulation of Charge Carrier Behavior in ZnO Photoelectrochemical Water Splitting

Photoelectrochemical water splitting via consumption of solar energy is considered an alternative approach to address both fossil resource and global warming issues. On the basis of the bottom-up technique, major strategies have been developed to enrich the complexity of nanostructures by incorporating various functional components to realize outstanding photoelectrochemical (PEC) performance for hydrogen evolution, such as high solar-to-hydrogen efficiency and long-term stability. In such a PEC system, each nanomaterial component individually, and more importantly, together with the formed interfaces, contributes to PEC performance elevation. Specifically, the two types of interfaces that have emerged, i.e., the interfaces between photoelectrodes and electrolytes (solid-liquid contact) and the interfaces inside photoelectrodes (solid-solid contact), have both been effectively engineered to facilitate charge separation and transportation and even enhance the antiphotocorrosion properties. A comprehensive understanding, summary, and review of such interface engineering protocols may provide novel and effective approaches for PEC system designing.