Facile synthesis of Mn, Ce co-doped g-CN composite for peroxymonosulfate activation towards organic contaminant degradation.

Peroxymonosulfate (PMS)-based advanced oxidation processes for wastewater treatment have received extensive attention in the past years. Here, a novel Mn, Ce co-modified g-CN (MnCe-CN) composite was successfully synthesized by one-step pyrolysis for activating PMS. The physical and chemical characterization of MnCe-CN/PMS was conducted, indicating that Mn and Ce were evenly distributed on g-CN and existed in the form of Mn-N structure and CeO, respectively. The MnCe-CN/PMS system could effectively degrade pollutants such as acetaminophen (ACT), methylparaben (MeP), p-nitrophenol (PNP), and 2,4-dichlorophenol (2,4-DCP). Among them, 2,4-DCP could be rapidly degraded, reaching 100% within 30 min. The masking experiments and electrochemical testing results revealed that 2,4-DCP was degraded via superoxide radicals (O˙-), singlet oxygen (O), and electron transfer path. The cyclic experiments and real water treatment experiments testified that the oxidative system had excellent stability and applicability. This study provides a facile synthetic method to fabricate bimetallic co-modified g-CN for the enhancement of PMS activation.