Rod-like BiVO4 with two-phase structure to boost photoelectrocatalytic degradation activity for tetracycline via the p-n junction

Abstract

Bismuth vanadate (BiVO4) as a potential photoanode is widely applied in photoelectrocatalytic (PEC) degradation flied. However, it is inhibited due to easy recombination of the photogenerated carries. Herein, rod-like morphology BiVO4 with monoclinic and tetragonal phase structure (R-BVO) are prepared using hydrothermal approach. Density functional theory (DFT) calculation confirms that the build-in electron field is constituted at contact interface of two-phase structure. Benefiting from the one-dimensional conduction of rod like morphology and the p-n junction formed by two-phase structure, R-BVO indicates outstanding photocurrent, the applied bias photo-to-current efficiency (ABPE) and the incident photoelectron conversion efficiency (IPCE). Compared with the single phase structure particle BiVO4 (P-BVO), the PEC degradation rate for TC of R-BVO is 96.4 %, which is 1.4 times of P-BVO. Equally importantly, the Ni foam is used as conducting substrate owing to its low cost and practicability, moreover, it is not only easy to determine catalyst dosage, but also ensures the tight contact between active substance and substrate, preventing the catalyst from peeling off in reaction. This study puts forward an adventurous strategy for designing effective photoanode materials.