Spinel Heterostructure Strategy with Electron Delocalization for Highly Active Fenton‐Like Catalysts in Wastewater Decontamination

ABSTRACT Developing heterogeneous Fenton‐like systems that balance decontamination efficiency and stability remains challenging for wastewater treatment. This work presents a sulfur doping‐induced strategy for constructing MnCo 2 O 4 /MnCo 2 S 4 spinel heterostructure, enabling efficient and stable Fenton‐like reaction via interfacial electronic structure modulation. The heterostructure/peroxymonosulfate (PMS) system achieved over 99% degradation of ofloxacin within 5 min (kinetic constant of 1.25 min −1 ), surpassing reported spinel or heterostructure catalysts (0.02–1.07 min −1 ). It showed exceptional anion tolerance with a radical‐nonradical synergistic mechanism dominated by SO 4 · − and high‐valent metal species. The catalyst maintained < 5% activity loss over four cycles and fully regenerated via thermal treatment. Experimental and DFT calculations revealed that the heterostructure triggers Co‐Mn charge redistribution to enhance interfacial Co─O covalency, inducing electron delocalization to promote electron transfer and PMS activation. Specifically, strengthened σ‐type orbital hybridization between Co 3d and PMS‐O 2p, coupled with weakened metal‐oxygen bonding strength, synergistically enhances activation and intermediates dissociation, thereby synchronously reducing the activation energy barriers for SO 4 · − and Co(IV) = O generation. Practical application demonstrated that the system removed 71% of ofloxacin in high Cl − waste leachate within 5 min, over 200% higher efficiency than MnCo 2 O 4 /PMS systems. This interfacial design strategy offering a promising pathway for robust Fenton‐like catalysts in real wastewater treatment.