Recent advances in the use of metal oxide-based photocathodes for solar fuel production

Harvesting solar energy for the production of clean fuel by a photoelectrochemical system is a very attractive, yet a challenging task. This review focuses on the recent efforts done to tailor metal oxide-based photocathode materials for the solar-driven hydrogen production. The materials are classified into three categories: simple oxides, complex oxides, and photocathodes used in p-n self-biased heterojunction cells. Generally, three strategies have been recommended to tailor p-type metal oxide semiconductors to meet the requirements for efficient solar-driven water splitting, namely (1) coating the p-type metal oxide either with a protective layer or a dye, (2) using co-catalyst, and (3) merging the p-type material with an n-type photoanode with the proper optical and electrical properties. In the light of those strategies, the optical, structural, and photoelectrochemical characteristics of such assemblies are discussed. (C) 2014 AIP Publishing LLC.