A novel magnetic Fe, N co-doped Ce-MOFs derived carbon as a peroxymonosulfate activator for the degradation of tetracycline hydrochloride: Performance and activation mechanism

Abstract

The activation of peroxymonosulfate (PMS) using metal-organic frameworks (MOFs) has garnered significant interest in the field of wastewater treatment. However, the environmental challenges associated with traditional methods for synthesizing MOFs precursors, such as the requirement for high temperatures and pressures, remain. Furthermore, the catalytic performance and stability of mono-metallic materials are areas needing enhancement. This work successfully synthesized a novel magnetic Fe-Ce bimetallic N-doped porous MOF material (Fe/Ce@5MNC). The optimized Fe/Ce@5MNC exhibited a higher specific surface area and a more extensive pore structure, as verified by various characterization techniques. Moreover, the synthesis process of the precursor is simpler, energy-saving, and relatively environmentally friendly. Notably, the synergistic effect between Fe and Ce, coupled with the presence of multiple active sites such as FeNx and graphite N, enabled Fe/Ce@5MNC to decompose 86.4 % of TCH within 30 min, marking a 31.4 % increase over Ce@NC. After four cycles, the catalyst maintained good surface stability, with the degradation efficiency remaining at 67.7 %. Quenching and electron paramagnetic resonance (EPR) experiments confirmed that the main degradation mechanisms are singlet oxygen (1O2) generation and electron transfer. This study presents a new method for synthesizing efficient Fe, N co-doped magnetic bimetallic PMS activators and designing carbon catalysts for deep oxidation.