Plasma photo-Fenton-like catalysis with iron-doped g-C3N4 enhances chloramphenicol degradation in an atmospheric dielectric barrier discharge system

Herein, elemental iron-doped graphite carbon nitride (Fex/g-C3N4) were synthesized and employed to initiate plasma photo-Fenton-like process for enhancing chloramphenicol degradation in atmospheric dielectric barrier discharge. Characterizations and density functional theory (DFT) calculations of prepared catalysts reveal that elemental iron is bound in nitrogen pots of g-C3N4, promoting carrier separation and serving as Fenton-like catalytic sites. Under optimized conditions, Fe0.9/g-C3N4 increases the degradation percentage of chloramphenicol from 78.67 % to 96.40 %. The catalyst exhibits favorable suitability across a broad solution pH range from 3 to 11. Reactive oxygen species measurements and quenching experiments demonstrate that hydroxyl radical is generated in plasma photo-Fenton-like process with Fe0.9/g-C3N4, while superoxide anion emerges as the pivotal reactive species in free radical chain reactions. Furthermore, degradation pathways of chloramphenicol are proposed based on the identification and reaction energy barrier of degradation products. Ecotoxicity evaluations of chloramphenicol degradation indicate that plasma photo-Fenton-like with Fe0.9/g-C3N4 effectively eliminates the ecotoxicity of chloramphenicol.