Abstract: The development of a combined photocatalytic system with peroxymonosulfate (PMS) has great potential applications in the degradation and treatment of aqueous organic pollutants. Herein, a Co₃O₄-ZnO/rGO was prepared by a hydrothermal method using cobalt acetate, zinc acetate, and reduced graphene oxide (rGO) as the main raw materials. The physical and chemical characteristics of the obtained catalyst were analyzed using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Fourier transform infrared (FT-IR). The photocatalytic features and capacities of the catalytic materials to activate PMS were investigated. Co₃O₄-ZnO/rGO exhibited stronger photocatalytic activity and ability to activate PMS than Co₃O₄/rGO or ZnO/rGO, and significantly improved the ability of PMS and photocatalysis to synergistically degrade rhodamine B (RhB), with a degradation rate of 90.40% within 40 min. The mechanism of RhB degradation was proposed based on characterization of materials, evaluation of RhB degradation efficiency, and analysis of the active species involved. The unique particle/sheet structure of Co₃O₄-ZnO/rGO provides a large number of active sites, and the formation of heterojunctions between Co₃O₄ and ZnO improves carrier separation and transport in the reaction system. Our study offers a reference for designing more effective heterojunction catalysts based on the combination of PMS and photocatalytic technology.

Co₃O₄-ZnO/rGO催化剂的制备及在硫酸盐自由基光催化降解罗丹明B的应用

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