Ligand-controlled electrochemiluminescence generation from CdSe/CdS/ZnS core/shell/shell quantum dots  

作　　者：Hui Sun Zhiyuan Cao Haiyan Qin Xiaogang Peng Bin Su 

机构地区：[1]Key Laboratory of Excited-State Materials of Zhejiang Province,Department of Chemistry,Zhejiang University,Hangzhou 310058,China

出　　处：《Nano Research》2024年第8期7776-7785,共10页纳米研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.22125405 and 22074131).

摘　　要：The CdSe/CdS/ZnS core/shell/shell quantum dots(QDs)with strong exciton confinement have manifested themselves as competitive light-emitting materials in electrochemiluminescence(ECL).However,cathodic ECL generation by these QDs requires the injection of electron and hole from solid electrode and electrogenerated radicals(for example SO_(4)•^(−)),which is inevitably influenced by not only the inorganic structure of QDs but also the organic ligands on the surface.In this work we aimed at studying the impact of surface organic ligands on ECL performance of CdSe/CdS/ZnS QDs.When changing the surface ligand from oleate to acetate,we phenomenologically observed the positive shift of ECL onset potential by ca.200 mV and the increase of ECL intensity by~100 times,suggesting that a short ligand is more favorable for ECL generation.To further comprehend the ligand effect,we measured the charge injection kinetics using potential-modulated,time-resolved photoluminescence,and thinlayer spectroelectrochemistry techniques.The electron and hole injection into QDs were found to be accelerated by 2–20 times if shortening the ligand from oleate to acetate,confirming the significant impact of surface ligands on ECL performance of QDs.The study is expected to provide guidance on how to design surface functionalized QDs for specific applications such as ECL immunodiagnosis,photocatalysis,and photovoltaics.

关 键 词：ELECTROCHEMILUMINESCENCE quantum dots SPECTROELECTROCHEMISTRY surface ligands charge injection charge transfer 

分 类 号：TB383[一般工业技术—材料科学与工程]