摘要
巯基酸是一种常用的量子点表面配体,对量子点的光电属性和催化活性具有重要影响.用宽带和频光谱(BBSFG)研究巯基酸分子(HS-(CH2)n-COOH,n=2,5,10)在Au膜和CdS量子点表面的排列方式.结果表明:在Au膜表面,3种自组装巯基酸单分子膜都是较有序的排列,可以检测到与巯基和羧基相连的2个亚甲基的C-H振动和频谱峰.而在CdS量子点表面,短链的巯基丙酸和巯基己酸处于较无序的混乱包覆状态,检测不到C-H振动和频谱峰;但长链的巯基十一烷基酸在CdS量子点表面呈较有序的类似反胶束状的排列,可以检测到与羧基相连的亚甲基的C-H振动和频谱峰.
Mercaptocarboxylic acids(MPAs)are one of the commonly used ligands for the surface capping of quantum dots(QDs),which exert important influence on the photoelectric properties and catalytic activity of QDs.The arrangement of the MPAs(HS-(CH2)n-COOH,n=2,5,10)on the surface of Au film and CdS QDs have been studied with broadband sum frequency generation(BB-SFG)spectroscopy in this study.In the BB-SFG spectra,the C-H stretching modes of two methylene groups adjacent to the mercapto and the carboxyl group can be detected from all of the three MPAs on the Au surface.On the surface of CdS QDs,no resonant BB-SFG band from the surface MPAs is observed for HS-(CH2)2-COOH and HS-(CH2)5-COOH.For HS-(CH2)10-COOH on CdS QDs,resonant BB-SFG bands corresponding to the C-H stretching of the methylene adjacent to the carboxyl are observed.These results show that all of the three MPAs are orderly packed on the flat Au surface;short-chain MPAs are disorderly wrapped on the CdS QDs,and the long-chain MPA is adsorbed with a well-ordered arrangement,similar to trans-extended bundles on the QDs.
作者
刘晨西
吴雪娇
何玉韩
郭伟
杨亨婷
刘晓琳
王朝晖
LIU Chenxi;WU Xuejiao;HE Yuhan;GUO Wei;YANG Hengting;LIU Xiaolin;WANG Zhaohui(College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China;Key Laboratory of Spectrochemical Analysis and Instrumentation,Ministry of Education,Xiamen University,Xiamen 361005,China;Collaborative Innovation Center of Chemistry for Energy Materials,Xiamen University,Xiamen 361005,China)
出处
《厦门大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第3期428-433,共6页
Journal of Xiamen University：Natural Science
基金
国家重点研发计划(2017YFA0206500,2016YFA0200702)
国家自然科学基金(21327901)。
关键词
宽带和频光谱
CDS量子点
排列方式
巯基酸分子
broadband sum frequency generation spectroscopy
CdS quantum dots
arrangement mode
mercaptocarboxylic acid
作者简介
通信作者:王朝晖,zhwang@xmu.edu.cn。
