Photo-Fenton Degradation of Tetracycline and Photoelectrochemical Properties of ZnFe<sub>2</sub>O<sub>4</sub>@ZnWO<sub>4</sub> Heterostructure Composite Coupling
Zhiming Li, Zhiqiang Wei, Meijie Ding, Qingsong Yu, Jinglong Bai, Huining Zhang
Abstract
Problems such as bacterial resistance caused by tetracycline antibiotics pose a serious threat to human production and life and ecosystems. We prepared ZnFe 2 O 4 @ZnWO 4 heterojunction nanocomposites using hydrothermal and coprecipitation methods. The micromorphology, structure, and photoelectrochemical properties were analyzed. In combination with the presence of H 2 O 2, the photo-Fenton activity of the antibiotic tetracycline at high concentration was tested under visible light irradiation, and its catalytic mechanism was investigated. The results showed that the composition of the composite heterojunction improved the catalytic activity of the catalyst. At a pollutant concentration of 50 mg L –1 and pH 5, 30% ZnWO 4 /ZnFe 2 O 4 degraded 92.1% of tetracycline in 60 min with a degradation rate of 0.0295 min –1, which was 6.7 times higher than that of pure ZnFe 2 O 4 . The results of free radical trapping experiments and electron spin resonance techniques indicated that hydroxyl radical (•OH) and superoxide radical (O 2 – ) played important roles in the photo-Fenton degradation of tetracycline. Notably, the catalyst maintained a high degradation rate (80%) after five cycles. ZnFe 2 O 4 introduced in this article may provide a promising strategy for achieving strong light absorption and is authoritative in meeting future environmental requirements.