基于氰基化9-苯基芴衍生物的激基复合物发光与性质研究  

Exciplex Emission and Property Investigation Based on Cyano-substituted 9-Phenylfluorene Derivative

作　　者：曹洪涛 侯鹏飞 曹庆 李延昂 汪莎莎 解令海 Cao Hongtao;Hou Pengfei;Cao Qing;Li Yanang;Wang Shasha;Xie Linghai(State Key Laboratory of Organic Electronics and Information Displays,College of Materials Science and Engineering,College of Chemistry and Life Sciences,Nanjing University of Posts&Telecommunications(NUPT),Nanjing 210023,China)

机构地区：[1]南京邮电大学材料科学与工程学院/化学与生命科学学院,有机电子与信息显示国家重点实验室,南京210023

出　　处：《化学学报》2022年第11期1476-1484,共9页Acta Chimica Sinica

基　　金：中国博士后科学基金面上项目(No.2022M711684);江苏省高校自然科学研究面上项目(No.22KJB430036);江苏省低维材料化学重点实验室2021年开放课题(No.JSKC20022);南京邮电大学校级自然科学基金(Nos.NY221084,NY221085)资助

摘　　要：激基复合物发光器件因给、受体材料掺杂比例易调且易实现小的单线态-三线态能隙差等优势,在发展工艺简单、性能高效的有机发光二极管方面显示出很大的应用潜力.针对目前激基复合物受体材料的种类仍较为匮乏,器件性能仍需改善等问题,本工作设计合成出新型基于9-苯基芴的电子受体材料(TCNDPFCz)用于构筑激基复合物发光器件.实验表明,受体分子TCNDPFCz与给体分子1,1-bis[(di-4-tolylamino)phenyl]cyclohexane(TAPC)掺杂后(TAPC:TCNDPFCz)呈现明显的激基复合物发光,其光致发光效率为54%,电流效率为27.2cd·A^(-1),功率效率为32.9lm·W^(-1),外量子效率为12.5%.经分析,我们推测激基复合物TAPC:TCNDPFCz形成的过程得益于TCNDPFCz具有很强的吸电子能力.本工作表明9-苯基芴可以作为骨架单元来构筑受体分子,为开发新型电子受体材料提供了新策略.Exciplex-thermally activated delayed fluorescence(exciplex-TADF)devices have displayed great application potential in developing organic light-emitting diodes(OLEDs)with simple-process and high-performance,because the doped ratio of electron donor and acceptor in exciplex device is easily controlled as well as repeated,and small singlet-triplet energy splitting(ΔEST)can be easily achieved for harvesting TADF.However,the current reported electron acceptors are still rare,which mainly focus on traditional electron-attracting structures,such as nitrogen-heterocycles,triarylboron,triazinearenes and diphenylphosphine oxides,etc.Therefore,it is highly desirable to construct new acceptor structures for improving exciplex device performance.In this work,we design and synthesize a novel cyano-substituted 9-phenylfluorene derivative(TCNDPFCz)as an electron acceptor to form exciplex emission through adopting 1,1-bis[(di-4-tolylamino)phenyl]-cyclohexane(TAPC)as an electron donor.Our experimental results show that the mixed system(TAPC:TCNDPFCz)exhibits bright exciplex emission at 535 nm and a favourable photoluminescence quantum yield(PLQY)of 54%.Subsequently,temperature-dependent transient fluorescence decay experiment is carried out,which indicates that the TAPC:TCNDPFCz film possesses TADF feature.It is suggested that the satisfactory PLQY value benefits from the exciplex-TADF of TAPC:TCNDPFCz.The low-temperature fluorescence and phosphorescence measurements are also performed and show that the TAPC:TCNDPFCz film displays smallerΔEST value of 0.05 eV.It is obvious that such smallΔEST value promotes the reverse intersystem crossing from non-radiative triplet state to radiative singlet state of TAPC:TCNDPFCz,thus achieving TADF process.Additionally,electrochemical measurement shows that the TAPC:TCNDPFCz system displays large driving force of 0.41 eV in its exciplex-formation processes,which implies that the exciplex-emission(TAPC:TCNDPFCz)can be realized easily.More than that,it indicates that the acceptor TCNDPFCz poss

关 键 词：9-苯基芴 激基复合物发光 延迟荧光 外量子效率 氰基取代 

分 类 号：TB34[一般工业技术—材料科学与工程] TN383.1[电子电信—物理电子学]