A surface-static strategy for constructing a core–shell MOF-derived Fe/Co catalyst for efficient peroxydisulfate activation toward tetracycline degradation

It remains challenging to fabricate bimetallic MOF-derived catalysts with efficient redox cycling to active peroxydisulfate (PDS) in advanced oxidation processes for antibiotic removal. Herein, a surface-static synthesis strategy was employed to prepare a bimetallic core–shell catalyst (M@Z(Co 3 Zn 1 )). This strategy retained its original morphology and established synergistic Fe 2 + /Fe 3+ and Co 2+ /Co 3+ redox cycles to facilitate PDS activation. As a result, the M@Z(Co 3 Zn 1 )/PDS system achieved 97.6% tetracycline (TC) removal within 60 min, with a corresponding k obs value of 0.05742 min −1 , which is significantly higher than those of Z(Co 3 Zn 1 ) (77.1% and 0.01922 min −1 ), M(Fe) (62.0% and 0.01184 min −1 ) and catalysts reported in previous studies. The system maintained excellent stability over five consecutive cycles with low metal leaching. Furthermore, an extreme gradient boosting (XGBoost) model was developed to accurately predict catalytic performance under different operating conditions, demonstrating the potential of machine learning for catalyst-system optimization in wastewater treatment. This work provides a new strategy for the structural regulation of bimetallic MOF-derived catalysts and highlights the integration of machine learning with catalytic process design for antibiotic-contaminated water remediation.