Linker aggregation engineering of TADF materials to tune carrierbalance for highly efficient organic LEDs with long operationallifetime  

作　　者：Zhen Zhang Rongrong Xia Ke Wang Youjun Wu Panpan Zang Xuemin Gan Zhangcheng Liao Bin Wei Peng Wu Stefan Bräse Zixing Wang 

机构地区：[1]Key Laboratory of Advanced Display and System Applications,Ministry of Education,Shanghai University,Shanghai,China [2]Institute of Organic Chemistry,Karlsruhe Institute of Technology(KIT),Karlsruhe,Germany [3]Institute of Biological and Chemical Systems-Functional Molecular Systems(IBCS-FMS),Karlsruhe Institute of Technology(KIT),Karlsruhe,Germany

出　　处：《Aggregate》2024年第5期385-393,共9页聚集体（英文）

基　　金：National Key R&D Program of China,Grant/Award Number:2022YFE0109000;National Natural Science Foundation of China,Grant/Award Number:21975152;China Postdoctoral Science Foundation,Grant/Award Number:2022M722028;Deutsche Forschungsgemeinschaft,Grant/Award Number:3DMM2O−EXC−2082/1−390761711。

摘　　要：Thermally activated delayedfluorescence(TADF)molecules are regarded as promis-ing materials for realizing high-performance organic light-emitting diodes(OLEDs).The connecting groups between donor(D)and acceptor(A)units in D–A type TADF molecules could affect the charge transfer and luminescence performance of TADF materials in aggregated states.In this work,we design and synthesize four TADF molecules using planar and twisted linkers to connect the aza-azulene donor(D)and triazine acceptor(A).Compared with planar linkers,the twisted ones(Az-NP-T and Az-NN-T)can enhance A–A aggregation interaction between adjacent molecules to balance hole and electron density.As a result,highly efficient and stable deep-red top-emission OLEDs with a high electroluminescence efficiency of 57.3%and an impressive long operational lifetime(LT_(95)∼30,000 h,initial luminance of 1000 cd m^(-2))are obtained.This study provides a new strategy for designing more effi-cient and stable electroluminescent devices through linker aggregation engineering in donor–acceptor molecules.

关 键 词：acceptor stacking balanced carrier transfer host materials long device lifetime thermally activated delayedfluorescence 

分 类 号：TN383.1[电子电信—物理电子学]