Crucial role of heterostructures in highly advanced water splitting photoelectrodes

Abstract Photoelectrochemical (PEC) water splitting, which is a clean hydrogen production method with a zero-carbon footprint, has been widely studied based on various materials. Heterostructure photoelectrodes have great importance in overcoming the limit of intrinsic properties of single material. Herein, we summarize the progress of heterostructure photoelectrodes in the recent years. The strategies in which heterostructure leads to improvement of PEC performances in the process of light absorption, charge transport, and interfacial charge transfer are demonstrated. The influence of heterostructures with respect to band structure, charge carrier dynamics, and photostability is amply discussed, and synergistic effects with nanostructures are finally suggested. This brief review presents significant advances in the design of highly advanced photoelectrodes.