One-dimensional bismuth vanadate nanostructures constructed Z-scheme photocatalyst for highly efficient degradation of antibiotics

Abstract

The construction of a solid-state carrier transport-prompted Z-scheme photocatalytic system represents a crucial possibility for green technology as it can achieve valid carrier separation/transfer in hybrid heterojunction, providing an innovative way to manage improved sunlight-driven photocatalytic performance over to conventional composites. Therefore, how to establish a photocatalytic Z-scheme complex with an appropriate position of energy band and redox capacity has been a research focus. Herein, spindle-shaped BiVO4/RGO/g-C3N4 nanocomposites were integrated with a one-step hydrothermal method by using sodium oleate as the surfactant. Benefitting from the unique spindle-shaped BiVO4 and ultrathin g-C3N4 nanosheets, the composite photocatalysts possess a large aspect ratio, leading to solid light capturing ability and considerable surface areas. For photocatalytic degradation of antibiotics, the tetracycline (TC) and ciprofloxacin (CIP) photodegradation rates are as high as 81.10% and 94.8% in 60 min, respectively. The photocatalytic performance of these ternary composites is superior to other photocatalyst counterparts. The spindle-shaped BiVO4 nanostructures have superior optical performance, oriented carrier transport and photooxidation response, addressing the short carrier diffusion length issue that could cause a visible recombination rate for the electron-hole couple in the conventional BiVO4 photocatalyst. It is demonstrated that the enhanced photocatalytic performance refers to the improved photogenerated electron-hole pairs and rapid carriers transfer in the composite photocatalysts under visible-light irradiation. This study affords a promising platform for preparing other Z-scheme photocatalysts with high catalytic performance for the degradation of antibiotics and renewable solar energy collection in biochemical transformation.