Preparation of ZnO/Cu2O Composite Particles and Its Degradation of Ciprofloxacin: Analysis of Degradation Performance and Active Species

Abstract

At present, the water pollution caused by antibiotics has seriously affected the ecological balance and human health. The development of a novel and efficient visible-light-responsive semiconductor photocatalysts is of great significance for the degradation of ciprofloxacin by visible light. In this study, solvothermal method was used to prepare ZnO and ZnO/Cu2O composite particles. The effects of ZnO addition on the microstructure, surface morphology and photoelectric properties of composite particles were studied by XRD, XPS, SEM, BET and UV-Vis techniques. The kinetics of photocatalytic degradation of ciprofloxacin by ZnO/Cu2O composite particles and the contribution of different active species in the degradation process were studied. The results show that the purity of the prepared product is high. ZnO/Cu2O has an octahedral morphology. Compared with Cu2O, ZnO/Cu2O has a clear difference, the absorbance is reduced, the band gap is increased, and the surface fitting resistance is significantly reduced. Among them, R3 sample has highest purity and degree of recombination, the surface fitting resistance is the smallest, the separation efficiency of photogenerated electrons and holes is improved, and the photocatalytic performance is improved. The degradation rate of ciprofloxacin by R3 sample is 80.4%, and the degradation of ciprofloxacin conforms to the first-order kinetic equation. After 5 repeated experiments, the ciprofloxacin degradation rate can still reach 75.3%, indicating that the composite material has good stability and reusability. Studies on active species in the process of degradation showed that ·OH played a major role in the degradation of ciprofloxacin.