Enhanced FeIV═O Generation via Peroxymonosulfate Activation by an Edge‐Site Engineered Single‐Atom Iron Catalyst

Abstract As an oxidant, the ferryl‐oxo complex (Fe IV ═O) offers excellent reactivity and selectivity for degrading recalcitrant organic contaminants. However, enhancing Fe IV ═O generation on heterogeneous surfaces remains challenging because the underlying formation mechanism is poorly understood. This study introduces edge defects onto a single‐atom Fe catalyst (FeNC‐edge) to promote Fe IV ═O generation via peroxymonosulfate (PMS) activation. In the presence of PMS, the FeNC‐edge catalyst at a low dose (20 mg L −1 , equivalent to 0.14 mg L −1 Fe) exhibits unprecedented activity for organic contaminant degradation. Electrochemical analysis, in situ Raman spectroscopy, and Fe IV ═O probe experiments confirm that Fe IV ═O generation is enhanced on the surface of FeNC‐edge. Density functional theory calculations reveal that the introduced edge sites concentrate electron density on active Fe atoms, facilitating charge transfer from Fe to PMS. Notably, FeNC‐edge immobilized on a polymeric membrane functioned as a continuous‐flow oxidation system with efficient catalyst recycling and minimal Fe leaching.