▎ 摘 要
This work is dedicated to achieving the high mineralization efficiency of oxytetracycline (OTC) in a dissolved oxygen (DO) activated Fenton-like system by constructing a catalyst with unique catalytic performance. Three-dimensional graphene anchored nZVI hybrid MnO2 (3D-rGO@nZVI/MnO2) with layered and porous structures was synthesized and characterized by field emission scanning electron microscopy coupled with an energy dispersive spectrometer (SEM-EDS), Brunner-Emmet-Teller (BET) analysis, X-ray diffraction (XRD) measurement and Raman spectroscopy. The experimental results showed that the removal efficiency of OTC could reach 100.0% with outstanding TOC decrease of 84.0% at natural pH in the 3D-rGO@nZVI/MnO2-DO system. More-over, negligible harmful intermediates were detected by ultra-performance liquid chromatography-mass spec-trometry (UPLC-MS) after the reaction in the 3D-rGO@nZVI/MnO2-DO system. Reactive oxygen species (ROSs) detection, electrochemical measurements and X-ray photoelectron spectroscopy (XPS) analysis confirmed that the elimination mechanism of OTC was the unique catalytic degradation caused by the synergism of center dot OH and 1O2. The unprecedented synchronous generation of center dot OH and 1O2 by DO activation provides an innovative strategy for further exploration of Fenton-like system toward more effective degradation of organic pollutants.