Photocatalytic degradation of ofloxacin by ZnO/CsxWO3composite synthesized by two-step method: A kinetic study

Abstract

The composite of ZnO/CsxWO3with heterojunction was prepared by a two-step solvothermal method and the degradation of ofloxacin solution under full-spectrum light irradiation was carried out to evaluate the performance. The composites were characterized by XRD, SEM, EDS and UV-Vis-NIR reflectance. The result shows that the prepared composite has an ideal optical absorption in the spectral region of 200–2500[Formula: see text]nm and higher photocatalytic performance compared with ZnO and CsxWO3. Moreover, [Formula: see text], [Formula: see text]OH and [Formula: see text][Formula: see text] radicals are determined to be the active species. It is suggested that the heterojunction between ZnO and CsxWO3for ZnO/CsxWO3composite is important for improving the charge separation and thus restraining the recombination of photogenerated electrons and holes. Photodegradation of ofloxacin catalyzed by ZnO/CsxWO3followed the first-order kinetics and the degradation rate of ZnO/2CsxWO3was about two times higher than those of CsxWO3and ZnO.