The enhanced mechanism of Fe(III)/H2O2 system by N, S-doped mesoporous nanocarbon for the degradation of sulfamethoxazole

Fenton-like technology has been widely used in the field of water treatment as an advanced oxidation processes (AOPs), and a multitude of non-homogeneous catalysts have been reported effectively to enhance it. Herein, nitrogen and sulfur co-doped nanocarbon materials (NSC) was designed and synthesized, which formed a unique mesoporous structure and abundant functional groups on the surface. It exhibits superior catalytic performance to enhance the Fe(III)/H 2 O 2 system for sulfamethoxazole (SMX) degradation, k obs is 18 times higher than Fe(III)/H 2 O 2 system after the introduction of NSC under the same experimental conditions. Also, the working pH of Fe(III)/H 2 O 2 system was broadened by NSC. Quenching and probe experiments demonstrate that hydroxyl radical (∙OH) was the dominant active species. Both dissociative and surface-bound iron species were observed, which indicates direct reduction and in-situ binding of Fe(III), respectively. Further investigation found nitrogen and sulfur co-doped attribute to the formation of abundant functional groups, the C O bond and C S C bond on the surface of NSC result in the directly reduce of Fe(III), while –COOH contributes to the in-situ binding. The intermediates and possible degradation pathway of SMX degradation were proposed based on the results of liquid chromatography-quadrupole time of flight-mass spectrometer (LC-QTOF-MS). The results of cycling and co-existing ions experiments demonstrate that NSC has outstanding potential for application. This work provides a novel insight into the sustained removal of micropollutants from the aqueous environment based on the nanocarbon materials enhancing the Fenton-like oxidation.