Top-down fabrication of Ti doped BiVO4 nanosheets for efficient water oxidation under visible light

Abstract

BiVO₄ is one of the fascinating materials with excellent photocatalytic properties. A top-down approach composed of a solid state reaction and an ion exchange reaction is introduced to fabricate Ti doped BiVO₄ nanosheets. Ti doped BiVO₄ nanosheets exhibit a thickness of 3 nm with a lateral dimension as large as 2 μm. The optimal photocatalytic performance is achieved for BiV_0.98Ti_0.02O₄ with an O₂ evolution rate of 102.8 μmol h⁻¹ g⁻¹ under visible light, which is 6 times and 23 times higher than those of undoped nanosheets and bulk sample, respectively. The enhancement is attributed to the short diffusion length of the photogenerated carriers in the nanosheets, the effective suppression of direct radiative recombination and the increasing concentration of oxygen vacancies induced by the Ti dopant.