Engineering of Defect Modulation Enhances the Catalytic Degradation of Tributyl Phosphate Wastewater With Fe‐Doped BaZrO 3 Catalysts

ABSTRACT Oxygen vacancies (OVs) dominate the catalytic performance of perovskite oxides, yet their controllable preparation and surface activation are hard to achieve. Herein, a temperature‐controlled hydrogen reduction strategy was developed to treat B‐site Fe‐doped BZO (BFZO), which significantly enriches the surface oxygen vacancies (OVs) available for catalysis. The as‐prepared catalysts were applied in peroxydisulfate (PDS)‐driven Fenton‐like oxidation to degrade tributyl phosphate (TBP). We systematically studied how 500°C–900°C reduction temperatures alter Fe valence states, crystal structure, defect distribution, and catalytic activity, and clarified the structure‐activity relationship via XRD, Raman, and XPS characterizations. The results reveal that Fe doping triggers local lattice distortion. Elevated reduction temperature reduces Fe 3+ to Fe 2+ , triggering lattice oxygen loss and accumulating surface OVs. The catalyst reduced at 800°C possesses the maximum surface OVs content. At 80°C, the BFZO‐800 catalyst achieves a TOC removal of 41.79%, significantly higher than that of pristine BZO (29.22%) and unreduced BFZO (31.49%), owing to its enriched surface oxygen vacancies. This work offers a simple defect engineering route for perovskite catalyst design and guides Fenton‐like treatment of refractory organic wastewater.