Fabrication of multi-morphological Bi2O2(OH)NO3-BiVO4 Z-Scheme heterojunction for enhanced photocatalytic antibiotic removal performance

Abstract

Due to the suitable band gap, good stability, and convenient preparation, bismuth vanadate (BiVO4) is regarded as one of potential semiconductor photocatalyst. However, the practical application was restricted by low catalytic efficiency and the poor charge separation. To address these obstacles, a novel Bi-based Bi2O2(OH)NO3-BiVO4 heterogeneous composite was constructed and synthesized by a mild and convenient hydrothermal method. The results of XRD, SEM, XPS, and DRS characterizations indicated that the Bi2O2(OH)NO3-BiVO4 heterogeneous catalyst were prepared successfully. The as-synthesized Bi2O2(OH)NO3-BiVO4 composite had good surface properties and catalytic stability. The results of photocatalytic degradation demonstrated that the tetracycline removal capacity of Bi2O2(OH)NO3-BiVO4 composite was obviously enhanced, and the highest degradation rate could reach 95% after 90 min. The results of quenching experiments revealed that both active species of·OH,·O2- and h+ were involved in the Bi2O2(OH)NO3-BiVO4 catalytic system. The possible degradation pathways for tetracycline degradation were proposed by detecting the intermediate products of the degradation process using UPLC-MS technology. Under the interference of pH, common ions and organic matter in aquatic systems, the degradation system can still remain high degradation efficiency. It shows that the Bi2O2(OH)NO3-BiVO4 composite may be a promising photocatalyst for practical application. The current study provides new insight into developing more effective photocatalysts for antibiotic wastewater treatment.