Efficient peroxymonosulfate activation by magnetic Fe3O4/ZIF-67/Ti3C2Tx composites for tetracycline degradation

The inverse spinel-structured Fenton-like catalyst, magnetic Fe 3 O 4 nanoparticles, effectively activates peroxymonosulfate (PMS) to achieve the degradation of tetracycline (TC). However, a significant challenge remains in accelerating the Fe 3 + /Fe 2+ cycling during the activation process. Herein, Fe 3 O 4 /ZIF-67/Ti 3 C 2 T x (FCT) magnetic composite materials were synthesized via a wet chemical method and comprehensively characterized. The degradation of tetracycline hydrochloride (TC-HCl) was investigated by activating PMS with FCT, with a focus on the effects of charge transfer and transition metal ion valence state changes on sulfate radical (•SO 4 - )-based advanced oxidation processes. FCT-1 exhibited high efficiency in activating the PMS system for the removal of TC-HCl, achieving complete degradation of 10 mg/L TC-HCl within 10 minutes. A synergistic catalytic mechanism to activate PMS by FCT was proposed, primarily involving the electron-donating ability of Fe 2+ in Fe 3 O 4 , which enhances the Co 3+ /Co 2+ cycle, and the reduction capability of Ti 3 C 2 T x towards Fe 3+ . Additionally, FCT exhibited excellent recyclability and facilitated magnetic separation. Overall, this work provides new opportunities for developing efficient environmental catalysts with magnetic recoverability.