Mechanism of nitrogen impurity defect carbon promoter enhanced fenton-like reaction process
This study prepared a series of nitrogen-doped carbon materials by using ZIF-8 as a template to investigate their promotion performance and catalytic mechanism toward Fe3+/H2O2 system.The physical phase,morphological characteristics,and chemical composition of the promotor were analyzed with X-ray diffraction,Fourier transform infrared spectroscopy,Raman spectroscopy,and X-ray photoelectron spectroscopy.The results showed that the prepared promotor was abundant in pyridinic-nitrogen extrinsic defects,and the defect degree decreased with the increase of pyrolysis temperature during synthesis.Pollutant degradation experiments demonstrated that the addition of the promoter significantly facilitated the regeneration of Fe2+from Fe3+,and strengthened the performance of Fenton matrix on the degradation of coexisting organic compounds.Electron paramagnetic resonance analysis,reactive oxidation species(ROS)quenching,and electrochemical experiments indicated that ROS such as·OH,·O2-,and 1O2 were involved in the reaction system,of which OH played a major role.Detailed analysis of the promotion mechanism was conducted through X-ray photoelectron spectroscopy and quantum chemical calculations.The results indicated that the adsorption of Fe3+onto nitrogen defects on the surface of the promoter was accompanied by an electron transfer process from the promoter to adsorbed Fe3+,which was responsible for the regeneration of Fe2+.These findings provided a novel approach to addressing the key issue of low Fe3+/Fe2+cycling efficiency in the Fenton reaction,and provide a theoretical and data support for the coupling and application of carbon-based environmental functional materials with Fenton oxidation technology.
promoterFenton oxidizationcarbon defectreactive oxidation species
万方数据
维普
