Selective Deposition of Ag3PO4 on Specific Facet of BiVO4 Nanoplate for Enhanced Photoelectrochemical Performance

The modification of semiconductor photoanode is a reliable approach to enhance its water oxidation property. In this study, a BiVO4 nanoplate array photoanode is prepared via hydrothermal method, and the BiVO4/Ag3PO4 heterojunction is constructed on electron-dominant crystal faces and hole-dominant crystal faces of BiVO4 via different deposition methods, respectively. The hole-dominant crystal face is in favor of the transfer and reaction of holes, while the electron-dominant face is benefit for electrons. Compared with pristine BiVO4 photoanode, the performance of heterojunction photoanode based on the hole-dominant crystal face exhibits a significant increase, while that of electron-dominant face only shows a slight increase. It is demonstrated that the heterojunction on the hole-dominant face exhibits better performance, which is because the hole-dominant face can facilitate the separation of photo-generated holes and electrons more effectively than the electron-dominant face. This approach provides a new strategy to reasonably fabricate efficient heterojunction on photoanodes.