Synthesis and Modification of Zn‐doped TiO 2 Nanoparticles for the Photocatalytic Degradation of Tetracycline

The synthesis of Zn‐doped TiO 2 nanoparticles by solgel method was investigated in this study, as well as its modification by H 2 O 2 . The catalyst was characterized by transmission electron microscopy, X‐ray diffraction, Brunauer–Emmett–Teller, UV –visible reflectance spectra and X‐ray photoelectron spectroscopy ( XPS ). The results indicated that doping Zn into TiO 2 nanoparticles could inhibit the transformation from anatase phase to rutile phase. Zn existed as the second valence oxidation state in the Zn‐doped TiO 2 . Zn‐doped TiO 2 that was synthesized by 5% Zn doping at 450°C exhibited the best photocatalytic activity. Then, the H 2 O 2 modification further enhanced the photocatalytic activity. Zn doping and H 2 O 2 modifying narrowed the band gap and efficiently increased the optical absorption in visible region. The optimal degradation rate of tetracycline by Zn‐doped TiO 2 and H 2 O 2 modified Zn‐doped TiO 2 was 85.27% and 88.14%. Peroxide groups were detected in XPS analysis of H 2 O 2 modified Zn‐doped TiO 2 , favoring the adsorption of visible light. Furthermore, Zn‐doped TiO 2 modified by H 2 O 2 had relatively good reusability, exhibiting a potential practical application for tetracycline's photocatalytic degradation.