CuCoS/COFs composite to efficiently activate peroxymonosulfate: oxytetracycline degradation, reactive oxygen species, degradation routes and ecotoxicity.

Source: PubMed, NCBI / U.S. National Library of Medicine

Peroxymonosulfate (PMS)-based advanced oxidation technology is an efficient strategy for degrading refractory organic contaminants. Herein, a novel CuCoS/covalent organic framework composite (CuCoS/COFs) is synthesized via a two-step solvothermal route, and its catalytic performance in degrading oxytetracycline hydrochloride (OTC) through PMS activation is systematically investigated. The effects of catalyst composition, PMS dosage, catalyst dosage, initial OTC concentration, solution pH, and reaction temperature on degradation efficiency are explored. Under optimized conditions (catalyst 70 mg/L, PMS 400 mg/L, 25 °C, pH 5-9, OTC 15 mg/L), 99.54% of OTC is removed within 10 min. The composite shows strong pH adaptability, excellent reusability (over 85% efficiency after 5 cycles), and broad universality for various antibiotics and dyes. Quenching tests and EPR verify thatOH, , andOare the main reactive species. The Cu/Coredox cycle coupled with low-valent sulfur mediation constitutes the catalytic mechanism. TLC-MS identifies intermediates and establishes three degradation pathways. Ecotoxicity prediction and wheat germination experiments confirm significantly reduced toxicity of degradation products. This study shows promising application prospects in organic wastewater treatment.