Modulating Electron Distribution by Codoping N and B on Carbon Surface to Enhance Catalytic Ozonation Performance for Efficient Decontamination

Carbon-based catalysts have been widely applied in catalytic ozonation because of cost-effectiveness. However, the catalytic ozonation efficiency of carbon-based catalysts is low in decontamination because of the limited reactive sites on the pristine catalyst surface. Herein, a carbon-based catalyst coated on γ-Al₂O₃ demonstrating exceptional synergistic performance was synthesized by electron-rich nitrogen (N) and electron-deficient boron (B) codoping. Notably, the pseudo first-order reaction rate for atrazine (ATZ) degradation with B and N codoping of carbon-coated γ-Al₂O₃ (BNC/γ-Al₂O₃) was 0.29 min^-1, which was 6.19, 6.93, and 4.48 times greater than those of carbon-coated γ-Al₂O₃, N-doped carbon-coated γ-Al₂O₃, and B-doped carbon-coated γ-Al₂O₃, respectively. Mechanistic investigations reveal that N doping enhances the reactivity of the sp² carbon lattice by increasing surface electronegativity, while B doping introduces unpaired electrons and reactive -O-B-O- groups. Their codoping synergistically amplifies surface polarization, reshaping the electronic distribution and lowering the energy barrier for free radical generation, thereby accelerating micropollutant degradation. Furthermore, BNC/γ-Al₂O₃ catalysts exhibit excellent stability and hold significant potential for application in real wastewater matrices. This study provides a mechanistically grounded strategy for designing dual heteroatom-doped carbocatalysts, offering new opportunities for ozonation-based advanced oxidation processes in micropollutant decontamination.