Carbon nanodots:A metal-free,easy-to-synthesize,and benign emitter for light-emitting electrochemical cells  

作　　者：Yongfeng Liu Shi Tang Xiuyu Wu Nicolas Boulanger Eduardo Gracia-Espino Thomas Wågberg Ludvig Edman Jia Wang 

机构地区：[1]Department of Physics,UmeåUniversity,SE-90187 Umeå,Sweden [2]LunaLEC AB,Linnaeus väg 24,SE-90187 Umeå,Sweden [3]College of Physical Science and Technology,Yangzhou University,Yangzhou 225009,China

出　　处：《Nano Research》2022年第6期5610-5618,共9页纳米研究（英文版）

基　　金：support from J.C.Kempes Minnes Stipendiefond(No.SMK-1849.1);the Swedish Energy Agency(Nos.45419-1,46523-1,and 50779-1);the Swedish Research Council(Nos.2017-04380,2017-04862,2018-03937,and 2019-02345);the Swedish Foundation for Strategic Research,Stiftelsen Olle Engkvist Byggmästare(Nos.186-0637 and 193-0578);Bertil&Britt Svenssons stiftelse för belysningsteknik,the Swedish Foundation for International Cooperation in Research and Higher Education via an Initiation Grant for Internationalization(No.2019-8553)。

摘　　要：Light-emitting electrochemical cells(LECs)can be fabricated with cost-efficient printing and coating methods,but a current drawback is that the LEC emitter is commonly either a rare-metal complex or an expensive-to-synthesize conjugated polymer.Here,we address this issue through the pioneering employment of metal-free and facile-to-synthesize carbon nanodots(CNDs)as the emitter in functional LEC devices.Circular-shaped(average diameter=4.4 nm)and hydrophilic CNDs,which exhibit narrow cyan photoluminescence(peak=485 nm,full width at half maximum=30 nm)with a high quantum yield of 77%in dilute ethanol solution,were synthesized with a catalyst-free,one-step solvothermal process using low-cost and benign phloroglucinol as the sole starting material.The propensity of the planar CNDs to form emission-quenching aggregates in the solid state was inhibited by the inclusion of a compatible 2,7-bis(diphenylphosphoryl)-9,9’-spirobifluorene host compound,and we demonstrate that such pristine host-guest CND-LECs turn on to a peak luminance of 118 cd·m^(−2)within 5 s during constant current-density driving at 77 mA·cm^(−2).

关 键 词：carbon nanodot light-emitting electrochemical cell PHLOROGLUCINOL sustainable synthesis solution-based fabrication 

分 类 号：TM911.4[电气工程—电力电子与电力传动] TB383[一般工业技术—材料科学与工程]