γ-Fe₂O₃/ZnO@CNTs catalyzes photocoupled ozone degradation of2, 4-dichlorophenol in water

The chemical structure of endocriuptor 2,4-dichlorophenol (DCP) is stable, rendering the degradation efficiency of traditional water treatment technology relatively low. Photocoupled ozone advanced oxidation (PCO) technology possesses the capability to treat organic pollutants in water efficiently and rapidly, and may emerge as one of the effective treatment technologies for DCP. In this study, γ-Fe₂O₃ and ZnO were combined and co-supported on multi-walled carbon nanotubes (CNTs), thereby developing a catalyst, γ-Fe₂O₃/ZnO@CNTs, to catalyze the degradation of DCP in water through PCO. The results demonstrated that the catalyst could effectively facilitate the degradation of DCP. When the initial concentration of DCP is 20 mg/L, the dosage of O₃ is 72 mg/L/h, the dosage of the catalyst is 1 g/L, and the power density of the simulated sunlight source is 5000 W/cm², the removal rate of DCP within 90 minutes can reach 98.9%, and the degradation process follows the quasi-first-order kinetic law. Additionally, the degradation path of DCP was explored, and hydroxyl radical (•OH), electron hole (h⁺), and superoxide radical (\text•\rmO_2^ - ) were identified as the main oxidizing groups. This study offers a new treatment scheme for the effective treatment of DCP and other refractory organic pollutants.