Synergistic doping and defect engineering of CoS2 building electron cycle sites Co−N−Fe···SV for enhanced Fenton-like reaction

Herein, we synthesized well-dispersed N and Fe-doped CoS 2 (FNCS) with stable sulfur vacancies (S V ) for Fenton-like reaction. The characterization, experimental, and calculation results jointly unveiled the synergistic modification of heteroatoms and defects within FNCS constructed unique Co−N−Fe···S V sites, enabling synchronous activation of peroxymonosulfate (PMS) and dissolved oxygen (DO). Optimized S 3p-Co 3d orbital hybridization facilitated efficient electron cycling, generating both SO 4 •− radicals and singlet oxygen ( 1 O 2 ) at Co−N−Fe···S V sites. Consequently, the FNCS/PMS system, operating via a radical-nonradical synergistic mechanism, achieved an ultra-high pollutant degradation rate constant of 2.71 min⁻¹ , 3.77 times higher than radical-dominated CoS 2 /PMS, while retaining over 90 % of its initial activity after 10 h of operation with strong interference resistance. This work provides a clear perspective on regulating the electronic structure of active sites to synergistically activate multiple oxidants for enhanced Fenton-like catalysis.