Mof-Derived N-Doped Porous Carbons Activate Peroxomonosulfate to Efficiently Degrade Dyes Via Non-Radical Pathways

Carbon-based heterogeneous catalysts have attracted extensive attention due to the advantages of no metal leaching risk and environmental friendliness. However, the preparation of catalysts and the efficiency of their activation of PMS to degrade organic pollutants still need to be improved. This work synthesized a novel nitrogen-doped porous carbon material (NPCs) at different temperatures using MET-6 (ZnCl2: 1H-1,2,3-triazole) MOFs precursor through a one-step pyrolysis process. The optimized NPC-900 has a higher specific surface area and richer pore structure, confirmed by various characterization techniques. The NPC-900 was then utilized to activate peroxymonosulfate (PMS) to degrade organic dyes . The main catalytic active sites for RhB degradation by NPC -900 were the higher graphite N and sp2 hybrid carbons, with 99.75% degradation of rhodamine B (RhB). Radical scavenging experiments and electron paramagnetic resonance (EPR) spectroscopy revealed the presence of free radicals (SO4•−, •OH and O2•−) and non-free radicals (1O2and electron transfer) during the degradation of RhB, as the reaction time prolongs, the non-free radical gradually plays a dominant role. Additionally, using EIS-MS enabled the identification of RhB degradation intermediates, leading to the proposal of a potential mechanism for NPC-900 activation of PMS and the subsequent RhB degradation pathway. Therefore, this study synthesized a metal-free catalyst for activating PMS through a facile synthetic strategy, providing theoretical support for the efficient degradation of organic dyes in wastewater.