Activation of PAA at the Fe–Nx Sites by Boron Nitride Quantum Dots Enhanced Charge Transfer Generates High-Valent Metal-Oxo Species for Antibiotics Degradation

Advanced oxidation processes (AOPs) based on peracetic acid (PAA) offer a promising strategy to address antibiotic wastewater pollution. In this study, Fe-doped graphitic carbon nitride (g-C3N4) nanomaterials were used to construct Fe–Nx sites, and the electronic structure was tuned by boron nitride quantum dots (BNQDs), thereby optimizing PAA activation for the degradation of antibiotics. The BNQDs-modified Fe-doped g-C3N4 catalyst (BNQDs-FCN) achieved an excellent reaction rate constant of 0.0843 min–1, marking a 21.6-fold improvement over the carbon nitride (CN)-based PAA system. DFT calculations further corroborate the superior adsorption capacity of the Fe–Nx sites for PAA, facilitating its activation. Charge transfer mechanisms, with PAA serving as an electron acceptor, were identified as the source of high-valent iron-oxo species. Moreover, the BNQDs-FCN system preferentially targets oxygen-containing functional groups in antibiotic structures, elucidating the selective attack patterns of these highly electrophilic species. This research not only elucidates the pivotal role of high-valent iron-oxo species in pollutant degradation within the PAA-AOPs framework but also pioneers a wastewater treatment system characterized by excellent degradation efficiency coupled with low ecological risk, thereby laying the groundwork for applications in wastewater management and beyond.