Exogenous‐Oxidant‐Free Degradation of Pharmaceutical Residues via Continuous ROS Generation Over Fe/Mn Nanozymes Featuring Mn(IV) = O and Oxygen Vacancies

ABSTRACT The sustainable elimination of pharmaceutical residues from wastewater remains a critical environmental challenge. Herein, we report an aluminum matrix composite‐supported manganese ferrite (Almc–MFO) nanozyme that enables self‐driven reactive oxygen species (ROS) evolution from dissolved oxygen (DO) to degrade ofloxacin (OFX) without any external oxidants or energy input. The anchored MFO structure promotes interfacial electron transfer and stabilizes abundant oxygen vacancies, which synergistically facilitate the formation of Mn(IV) = O. The catalyst exhibits remarkable oxidative activity across pH 3–6, achieving 64%–95% degradation of OFX (1–10 mg L − 1 ) within 30 min and sustaining a continuous H 2 O 2 generation rate of 67.5 ± 4.0 µmol L − 1 h − 1 . DFT calculations further confirm that the *OOH intermediate, formed from O 2 on Mn sites, exhibits an H 2 O 2 ‐like O─O bond and low adsorption energy, prompting its desorption and selective conversion to H 2 O 2 . The Fe site exhibits a lower energy barrier in the rate‐determining step of H 2 O 2 dissociation into •OH and synergizes with the Mn site to achieve efficient H 2 O 2 turnover. This study provides a new theoretical foundation for designing advanced oxidation systems capable of self‐sustaining H 2 O 2 supply without exogenous oxidants.