烯胺酮硼配合物红光热活化延迟荧光材料及其有机电致发光性能  

Enaminone boron complexes-based red thermally activated delayed fluorescence materials and their organic electroluminescent properties

作　　者：栗华 吴晓甫[1] 童辉[1] 王利祥[1] LI Hua;WU Xiaofu;TONG Hui;WANG Lixiang(State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China)

机构地区：[1]中国科学院长春应用化学研究所高分子物理与化学国家重点实验室,长春130022

出　　处：《黑龙江大学自然科学学报》2021年第4期413-420,共8页Journal of Natural Science of Heilongjiang University

基　　金：国家自然科学基金资助项目(51833009,22075272,91833306,51973211)。

摘　　要：采用烯胺酮五氟苯基硼配合物与氰基修饰的烯胺酮五氟苯基硼配合物为受体单元,吖啶为给体单元,合成了两种红光热活化延迟荧光材料(EBC1和EBC2)。两种材料具有扭曲的给体-受体(D-A)结构、较小的单线态和三线态能量差(ΔEST)和较短的延迟荧光寿命。相比不含氰基的EBC1,含氰基的EBC2具有更低的LUMO能级,使掺杂膜的荧光发射从606 nm红移至622 nm;同时,ΔEST由0.09 eV减小到0.07 eV,延迟荧光寿命由1.75μs缩短到0.98μs。EBC1和EBC2在掺杂膜中的荧光量子产率分别为73.5%与25.0%。基于EBC1和EBC2的溶液加工型电致发光器件均实现了红光发射,发光峰分别位于622和643 nm,最大外量子效率分别达到12.5%和6.8%;基于EBC2器件的色坐标为(0.61,0.37),展示出烯胺酮硼配合物作为受体单元在构建高效纯红光TADF材料方面的发展潜力。Two red thermally activated delayed fluorescence materials(EBC1 and EBC2)were designed and synthesized by using enaminone pentafluorophenyl boron complex and cyano-modified enaminone pentafluorophenyl boron complex as acceptor units,respectively,coupling with acridine as donor unit.Both materials had distorted donor-acceptor(D-A)structures,small energy offsets between singlet and triplet states(ΔEST)and short delayed fluorescence lifetimes.Compared with EBC1 without cyano group,EBC2 with cyano group had lower LUMO energy level,leading to the red-shifted fluorescence emission from 606 nm to 622 nm.Meanwhile,theΔEST decreased from 0.09 eV to 0.07 eV,and the delayed fluorescence lifetime decreased from 1.75μs to 0.98μs.The photoluminescence quantum yields of EBC1 and EBC2 in the doped films were 73.5% and 25.0%,respectively.The solution-processed electroluminescent devices based on EBC1 and EBC2 showed the red emissions with the peaks at 622 nm and 643 nm,respectively.Both of devices had high performance with maximum external quantum efficiencies of 12.5% and 6.8%,respectively.It is noted that device based on EBC2 displayed the pure red emission with the CIE coordinate of(0.61,0.37).These results demonstrate that the enaminone boron complex is promising acceptor unit for the construction of high-efficiency pure red TADF materials.

关 键 词：烯胺酮硼配合物 延迟荧光 有机电致发光器件 红光发射 

分 类 号：TN383.1[电子电信—物理电子学]