Reduced monoclinic BiVO₄ for improved photoelectrochemical oxidation of water under visible light.

A monoclinic BiVO4 film was grown on a transparent conducting substrate for photoelectrochemical oxidation of water. A photocurrent up to 2.3 mA cm(-2) under visible light (λ > 420 nm) was achieved after treating the sample simply by electrochemical reduction followed by NaBH4. The high photocurrent is believed to be due to the improved carrier separation and transportation as a result of increased donor density.