ZIF-Derived Catalyst with Co–Co/Co–N Dual Active Sites for Boosting Mixed Pathway Decontamination in Fenton-like Catalysis

Pollutant degradation via radical-nonradical mixed pathways offers opportunities to break the reactivity-stability trade-off in heterogeneous Fenton-like catalysis for water treatment; however, a precise catalyst design to enforce such mixed pathways remains challenging. Herein, by using bimetallic ZIFs as the precursor, we fabricated a cobalt (Co)-based catalyst (Co_0.75Zn_0.25-NC) with dual active sites for peroxymonosulfate (PMS) activation, where the Co-Co site and Co-N site preferentially catalyze the sulfate radicals and single oxygen generation, respectively. The system exhibited superior pollutant degradation activity, especially for the lectron-rich pollutants like tetracycline, high PMS utilization efficiency, negligible interference by the complicated water matrix, and good adaptation to broad pH and water quality conditions. A stable operation of the corresponding catalytic ceramic membrane was also demonstrated, achieving ∼70% pollutant removal during the long-term continuous-flow operation. This work offers valuable references to guide the Fenton-like catalyst design toward sustainable and low-carbon water purification applications.