Fe-based carbonitride as Fenton-like catalyst for the elimination of organic contaminants

The Fenton-like process has been regarded as a clean and efficient approach to generate reactive oxygen species (ROS) to deal with the ever-growing environmental pollution. However, developing improved catalysts with adequate activity and stability remains a long-term goal for practical application. Herein, crystalline carbon nanotubes (CNTs) interconnected Fe/Fe₃C-doped nanoporous carbonitride (Fe-NC) was easily prepared by the pyrolysis of ZIF-8 confined with Fe³⁺. The obtained Fe-NCs possessed high degrees of graphitic carbon and nitrogen. Such Fe-NCs can enhance the activation of peroxymonosulfate (PMS) for the removal of multiple organic contaminants. The optimized Fe-NC/PMS system exhibited impressive catalytic performance, with a TOF as high as 4.43 min^-1 for 3BF degradation, and the removal efficiency of other dyes, phenols and antibiotics was up to 96.2% within 10 min. The removal efficiency of 3BF was 93.4% within 10 min with extremely low iron ions leaching (<0.052 mg/L) even after five cycles. In addition, the effects of pH on the catalytic performance demonstrated that the decomposition of 3BF exceeded 95.6% even when the initial pH varied from 5 to 10. We confirmed that SO₄^-, OH, O₂^- and ¹O₂ were generated in the catalytic system of Fe-NC/PMS, which played a critical role in degrading the organics. These findings provide new insights into the design of environmental-friendly Fenton-like catalysts with high efficiency and favorable stability in environmental remediation.