The application of metal-organic frameworks (MOFs)-based catalysts in Fenton-like reactions attracts increasing attention, however, improving the efficiency of these catalysts remains a challenge. Herein, a highly efficient peroxymonosulfate (PMS) activator (CuMg@Fe-MOFs-500) derived from MOFs was successfully synthesized. The results indicated that the Cu and Mg co-doping strategy employed in the fabrication of CuMg@Fe-MOFs-500 significantly enhanced the PMS activation performance, achieving a tetracycline (TC) degradation efficiency of 96.8 % within 60 min. The incorporation of the doped Mg and Cu significantly increased the contents of the oxygen vacancy (OV) and low-valent copper (Cu0 and Cu+), respectively. The interaction between the OV and Cu0/Cu+ became a key factor during the PMS decomposition process. Furthermore, for the first time, the OV content was observed to be positively and negatively linearly correlated with the reaction rate constant (k) and the charge transfer resistance (Rct) of the prepared PMS activators, respectively. Quenching experiments and electron paramagnetic resonance (EPR) tests demonstrated that the predominant reactive species generated during the PMS activation process were SO4•-, •OH, O2•-, and 1O2. It was also shown that the 1O2 primarily originated from O2•- disproportionation, and a self-quenching process between SO4•- and •OH was also observed. The intermediates produced during pollutant degradation induced by PMS-based Fenton-Like reaction exhibited reduced toxicity, as demonstrated by ecotoxicity analysis. This study presented a novel approach for the fabrication of catalyst derived from bimetallic doped MOFs, characterized by a high OV content, for the application in PMS-based Fenton-like reactions.
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