Nitrogen-doped pyrogenic carbonaceous matter facilitates azo dye decolorization by sulfide: The important role of graphitic nitrogen  

作　　者：Han-Qing Zhao Wen-Qiang Li Nannan Hou Lei Li Yiran Wang Peili Lu Yang Mu 

机构地区：[1]CAS Key Laboratory of Urban Pollutant Conversion,Department of Environmental Science and Engineering,University of Science and Technology of China,Hefei 230026,China [2]College of Environment and Ecology,Chongqing University,Chongqing 400044,China

出　　处：《Chinese Chemical Letters》2023年第2期230-235,共6页中国化学快报（英文版）

基　　金：the National Natural Science Foundation of China (Nos. U19A20108, 52025101, 51821006 and 51878637) for financially supporting this study。

摘　　要：Pyrogenic carbonaceous matter(PCM) catalyzes azo dye decolorization by sulfide, but the nitrogen doping catalytic mechanisms are poorly understood. In this study, we found that stagnate time of azo dye methyl orange(MO) decolorization was reduced to 0.54-18.28 min in the presence of various nitrogen-doped graphenes(NGs), remarkably lower compared to graphene itself. Particularly, graphitic nitrogen played a critical role in NGs-catalyzed MO decolorization by sulfide. Gas chromatography-mass spectrometry and in-situ surface Raman analysis demonstrated that doping nitrogen, especially graphite one facilitated reactive intermediate polysulfides formation. This is attributed to the improved electron conductivity through graphitic nitrogen doping, and the enhanced interactions between sulfide and carbon atoms bonded to graphitic nitrogen. This study not only provides a better understanding of PCM impact on transformations and fates of organic pollutants in natural environments, but also offer a new regulation strategy for more efficient wastewater treatment processes in PCM-catalyzed engineering systems.

关 键 词：Azo dye DECOLORIZATION Graphitic N Nitrogen doped graphene SULFIDE 

分 类 号：X703[环境科学与工程—环境工程]