掺N碳量子点负载于TiO_2的复合催化剂光解甲芬那酸研究  

Photocatalytic degradation mechanism of mefenamic acid by N-doped carbon quantum dots loaded on TiO_2

作　　者：张钱新 王枫亮 谢治杰 苏跃涵 陈平[1] 吕文英[1] 姚琨[1] 刘海津[2] 刘国光[1] ZHANG Qian-xin;WANG Feng-liang;XIE Zhi-jie;SU Yue-han;CHEN Ping;Lü Wen-ying;LIU Hai-jin;LIU Guo-guang(School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006 China;School of Chemistry and Environmental Science, Henan Normal University , Xinxiang 453007 China)

机构地区：[1]广东工业大学环境科学与工程学院,广东广州510006 [2]河南师范大学化学与环境科学学院,河南新乡453007

出　　处：《中国环境科学》2017年第8期2930-2940,共11页China Environmental Science

基　　金：国家自然科学基金(21377031;21677040);广东省自然科学基金(2016A030313697;河南省教育厅项目(13A610528)

摘　　要：以水热法成功制备了水溶性较好的N掺杂的碳量子点(NCQDs),并负载于P25制得P25/NCQDs复合材料;通过透射电子显微镜(TEM)、X射线衍射(XRD)和紫外可见光吸收光谱(UV-vis)等对P25/NCQDs复合材料进行形貌、元素和催化活性的表征.结果表明,NCQDs成功附着在P25上面,证实NCQDs的作用既使P25吸收光发生红移,又有效的扩大了P25的吸收光谱范围;催化剂活性实验研究表明P25/NCQDs对甲芬那酸(MEF)的光催化降解速率是同等条件下使用P25的6.4倍;碱性环境下有利于MEF的降解.实验同时研究了P25/NCQDs复合材料对MEF光催化降解的影响机制,通过对电子顺磁共振波谱(EPR)的分析,结果表明羟基是P25/NCQDs所产生的主要活性物质;使用异丙醇作为·OH的捕获剂,得出·OH对MEF降解的贡献率为82.9%.The water-soluble N-doped carbon quantum dots(NCQDs)were successfully prepared by hydrothermal method,which was used to dope titanium dioxide to form P25/NCQDs composite materials.The morphology,elemental and catalytic activity of NCP composites were characterized by transmission electron microscopy(TEM),X-ray diffraction(XRD)and UV-Vis Absorption Spectroscopy(UV-vis).The results show that the NCQDs was successfully attached to the surface of P25.NCQDs could let the absorption spectrum of P25redshift and enhance the light absorption range of P25.The photocatalytic degradation of mefenamic acid(MEF)by NCP was6.4times higher than bare P25under the same conditions.The effects of NCP composite on the photocatalytic degradation of MEF was also studied.The pH was favorable for the degradation of MEF in alkaline condition.The electron paramagnetic resonance(EPR)results show that the hydroxyl radical was the main active substance in the NCP system.The contribution rate of?OH for MEF degradation was82.9%through the quenching experiment by add isopropanol as scavenger.

关 键 词：甲芬那酸(MEF) 掺N碳量子点负载TiO2(NCP) 降解机制 羟基自由基 

分 类 号：X703[环境科学与工程—环境工程]