A Multistep Ion Exchange Approach for Fabrication of Porous BiVO4 Nanorod Arrays on Transparent Conductive Substrate

BiVO 4 is recognized as a promising semiconductor for photoelectrochemical (PEC) applications. However, the lack of synthesis methods to prepare high-quality nanostructural BiVO 4 film is rarely reported in the PEC field. In this study, we report a novel synthesis approach to prepare one-dimensional BiVO 4 nanowire arrays using a multistep ion exchange approach through a solvothermal–hydrothermal–annealing process. The resulting BiVO 4 electrodes showed a nanorod structure with high porosity. In particular, the aspect ratio surface of the BiVO 4 nanostructure was found favorable for its PEC application. The BiVO 4 nanostructure with an optimized synthesized condition showed efficient PEC water oxidation with a photocurrent of 1.67 mA/cm 2 at 1.83 V (vs RHE).