CdS纳米晶@碳点复合物膜的电致化学发光  

Electrochemiluminescence from CdS Nanocrystals@Carbon Dots Composite Film

作　　者：胡佳杰 朱媛[1] 宋华菊[1] 王颖[1] 单云[1] HU Jia-Jie;ZHU Yuan;SONG Hua-Ju;WANG Ying;SHAN Yun(Nanjing Key Laboratory of Advanced Functional Materials,Nanjing Xiaozhuang University,Nanjing 211171,China)

机构地区：[1]南京晓庄学院南京市新型功能材料重点实验室

出　　处：《无机化学学报》2020年第2期324-332,共9页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.21872071,21375067);江苏省自然科学基金(No.BK20161117)资助项目

摘　　要：采用热解柠檬酸法制备碳点(CDs),并将之与表面无包裹剂的CdS纳米晶(CdS NCs)超声复合制备CdS纳米晶@碳点(CdS NCs@CDs)复合物。研究了复合物膜阴极电致化学发光(ECL),探讨了CDs对CdS纳米晶膜ECL增强的机理。CDs分散性良好、尺寸在1.5~4 nm之间;与粒径约为4 nm的CdS纳米晶按体积比2∶3复合后,在360 nm光激发下复合物具有最强的荧光发射且表现为CDs的荧光。同时,复合物膜产生归属于激发态CdS纳米晶的最强的ECL发射,且ECL发光峰起置电势正移至-1.05 V。复合物膜的ECL发射是pH依赖的,在pH值为6时,复合物膜具有最大的ECL强度,为CdS纳米晶膜ECL强度的19倍。这种ECL增强源于CDs能束缚大量电子产生局域电场从而促进近邻CdS纳米晶激发态的形成与弛豫。Carbon dots(CDs)were prepared by pyrolysis of citric acid and composited with uncapped CdS nanocrystals(NCs)via ultrasonication to obtain CdS NCs@CDs composite.The cathodic electrochemiluminescence(ECL)from CdS NCs@CDs composite film was studied,and the mechanism underlying the ECL enhancement of CdS NCs film by CDs as well.The results showed that CDs were well dispersive and of 1.5~4 nm in diameter.When the volume ratio of CDs to CdS NCs with averagely size of 4 nm was 2∶3,the CdS NCs@CDs composite showed the strongest photoluminescence(PL)which originated from CDs under excitation of 360 nm.Simultaneously,the composite film generated the strongest ECL emission ascribed to excited CdS NCs.The composite film had a more positive set on potential(-1.05 V)for ECL generation.ECL emission of the composite film was pH dependent with the maximum ECL emission occurring at pH=6,meanwhile ECL was 19 times larger than that of CdS NCs film.This ECL enhancement was possibly because a large number of electrons can be trapped in CDs to generate localized electric field that facilitates formation and relaxation of excited states of neighboring CdS NCs.

关 键 词：半导体 碳 纳米粒子 复合物 电致化学发光 

分 类 号：O649.4[理学—物理化学]