N-doping offering higher photodegradation performance of dissolved black carbon for organic pollutants: experimental and theoretical studies

作     者：Yong GUO Mengxia CHEN Ting CHEN Ying GUO Zixuan XU Guowei XU Soukthakhane SINSONESACK Keophoungeun KANMANY Yong GUO;Mengxia CHEN;Ting CHEN;Ying GUO;Zixuan XU;Guowei XU;Soukthakhane SINSONESACK;Keophoungeun KANMANY

作者机构：Key Laboratory of Integrated Regulation and Resource Development on Shallow LakesMinistry of EducationCollege of EnvironmentHohai UniversityNanjing 210093China Key Laboratory of Environmental Engineering of Jiangsu ProvinceJiangsu Provincial Academy of Environmental ScienceNanjing 210036China State Key Laboratory of Pollution Control and Resource ReuseNanjing UniversityNanjing 210023China Central Environmental LaboratoryNatural Resources and Environment Research InstituteMinistry of Natural Resources and EnvironmentVientiane 999012Laos 

出 版 物：《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 (浙江大学学报（英文版）A辑（应用物理与工程）)

年 卷 期：2024年第25卷第4期

页      面：340-356页

核心收录：

学科分类：0809[工学-电子科学与技术（可授工学、理学学位）] 080902[工学-电路与系统] 08[工学] 0702[理学-物理学] 

基　　金：supported by the Project of the State Key Laboratory of Pollution Control and Resource Reuse Foundation Nanjing University(No.PCRRF21012)。 

主　　题：Dissolved black carbon(DBC) N-doping Organic pollutants Band gap Photodegradation 

摘      要：We investigated the influence mechanism of N-doping for dissolved black carbon(DBC)photodegradation of organic pollutants.The degradation performance of N-doped dissolved black carbon(NDBC)for tetracycline(TC)(71%)is better than that for methylene blue(MB)(28%)under irradiation.These levels are both better than DBC degradation performances for TC(68%)and MB(18%)under irradiation.Reactive species quenching experiments suggest that h and-O,are the main reactive species for NDBC photodegraded TC,while-OH and h*are the main reactive species for NDBC photodegraded MB.-OH is not observed during DBC photodegradation of MB.This is likely because N-doping increases valence-band(VB)energy from 1.55 eV in DBC to 2.04 eV in NDBC;the latter is strong enough to oxidize water to form-OH.Additionally,N-doping increases the DBC band gap of 2.29 to 2.62 eV in NDBC,resulting in a higher separation efficiency of photo-generated electrons-holes in NDBC than in DBC.AIl these factors give NDBC stronger photodegradation performance for TC and MB than DBC.High-performance liquid chromatography-mass spectrometry(HPLC-MS)characterization and toxicity evaluation with the quantitative structure-activity relationship(QSAR)method suggest that TC photodegradation intermediates produced by NDBC have less aromatic structure and are less toxic than those produced by DBC.We adopted a theoretical approach to clarify the relationship between the surface groups of NDBC and the photoactive species produced.Our results add to the understanding of the photochemical behavior of NDBC.