Photoelectrochemical water splitting under visible light over anti-photocorrosive In2O3-coupling ZnO nanorod arrays photoanode

摘要

In2O3 quantum dots with a high crystallinity were deposited on the surface of ZnO nanorods through a chemistry bath method. The resulting In2O3-sensitizing ZnO nanorod arrays not only exhibited enhanced photoelectrochemical activity for water splitting under visible-light irradiation, but also possessed anti-photocorrosion property. The photo-induced charge-transfer property of In2O3 could be improved greatly by coupling with ZnO. This observation demonstrated that the heterojunction at the interface between In2O3 and ZnO could efficiently reduce the recombination of photo-induced electron–hole pairs and increase the lifetime of charge carriers and therefore enhance the photo-to-current efficiency of the In2O3–ZnO nanocrystalline arrays. It reveals that the heterojunction construction between two different semiconductors plays a very important role in determining the dynamic properties of their photo- generated charge carriers and their photo-to-currentconversion efficiency.