Efficient activation of peroxydisulfate by FeNC for chloramphenicol degradation: Performance and mechanisms

In this study, a green Fe and FeN co-doped carbon nanocomposite catalyst (FeNC) was synthesized by a simple and economical method and applied to activate peroxodisulfate (PDS) for the efficient oxidation of chloram-phenicol (CAP). Characterization analysis found that the surface of Fe and FeN nanoparticles supported on nitrogen-doped carbon was wrapped by nitrogen-doped carbon nanosheets, forming a "core-shell" structure. The FeNC@PDS system has good catalytic activity, and the CAP degradation efficiency reaches 91.2% within 60 min. FeNC@PDS system exhibits excellent catalytic degradation performance under a wide pH range (2.4-8.3) and shows good reusability. The calculated % reaction stoichiometric efficiency (RSE) reached values up to 18.86%, which exceeds than those of various reported heterogeneous Fenton-like systems. Quenching experiments and electron paramagnetic resonance characterization confirmed that both free-radicals and non-radicals were involved in the activation of PDS by FeNC. In addition, the possible mechanism of the PDS activation by FeNC was proposed. Finally, the degradation pathway of CAP was determined based on the intermediates. This work provided a novel reference for the design of efficient heterogeneous catalysts to remove organic pollutants efficiently.