Atomically Dispersed FeO _x Species Functionalized Fe ₂ O ₃ Nano‐Island Clusters toward Efficient Fenton‐Like Catalysis

Abstract Iron‐based oxides, characterized by precisely engineered structural and surface properties, are extensively utilized as Fenton/Fenton‐like catalysts for water purification applications. Achieving atomic‐level control to simultaneously optimize catalytic processes and regulate the interplay between radical‐nonradical is highly desirable yet remains a significant challenge in FeO _x ‐based Fenton‐like catalysis. In this study, a novel approach is demonstrated to manipulate atomically dispersed FeO _x (reef) and Fe ₂ O ₃ nanoclusters (islands) through a laminated graphene (sea)‐controlled all‐solid‐state synthesis. The resulting “reef‐island‐sea” architecture, where atomically dispersed FeO _x species are confined by Fe ₂ O ₃ nano‐island clusters (Fe ₂ O ₃ NCs) and graphene, simultaneously optimizes three critical Fenton‐like processes: peroxydisulfate adsorption, O─O bond activation, and reactive species desorption. This unique configuration of atomically dispersed FeO _x @Fe ₂ O ₃ NCs@graphene serves as an integrated platform combining multifunctional active centers (oxygen vacancy‐rich Fe sites, C═O groups, and coordinatively unsaturated Fe species) to precisely modulate and enhance both radical and non‐radical pathways, thereby boosting Fenton‐like oxidation activity and stability. The graphene‐controlled all‐solid‐state strategy offers a promising avenue for constructing hybrid structures in monometallic catalysts, facilitating precise control over active sites for catalytic processes optimization and pathway regulation.