Recent progress in photoelectrochemical water splitting for solar hydrogen production

A water splitting photoelectrochemical (PEC) cell can convert solar energy to hydrogen fuels directly. The challenges for practical application are to fabricate photoelectrodes with high efficiency, good durability and low cost. In this review, we focus on recent progress of some promising photoelectrode materials, including BiVO₄${}_4$, α$\alpha$-Fe₂O₃, Ta₃N₅ photoanodes and Cu₂ZnSnS₄ photocathodes. Several new strategies to enhance the performance of a PEC cell, such as surface exfoliation, suppressing back reaction and loading dual-layer catalysts, are discussed.