Zhao Mengyu, Li Mengke, Li Wei, Du Songyu, Chen Zhenyu, Luo Ming, Qiu Yi, Lu Xumin, Yang Shengyi, Wang Zhichuan, Zhang Jiashen, Su Shi-Jian, Ge Ziyi
Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, 315201, Ningbo, P. R. China.
Angew Chem Int Ed Engl. 2022 Oct 17;61(42):e202210687. doi: 10.1002/anie.202210687. Epub 2022 Aug 19.
Constructing organic near-infrared (NIR) luminescent materials to confront the formidable barrier of "energy gap law" remains challenging. Herein, two NIR thermally activated delayed fluorescence (TADF) molecules named T-β-IQD and TIQD were developed by connecting N,N-diphenylnaphthalen-2-amine and triphenylamine with a novel electron withdrawing unit 6-(4-(tert-butyl)phenyl)-6H-indolo[2,3-b]quinoxaline-2,3-dicarbonitrile. It is confirmed NIR-TADF emitters concurrent with aggregation-induced emission effect, J-aggregate with intra- and intermolecular CN⋅⋅⋅H-C and C-H⋅⋅⋅π interactions, and large center-to-center distance in solid states can boost the emissive efficiencies both in thin films and non-doped organic light-emitting diodes (OLEDs). Consequently, the T-β-IQD-based non-doped NIR-OLED achieved the maximum external quantum efficiency (EQE ) of 9.44 % with emission peak at 711 nm, which is one of the highest efficiencies reported to date for non-doped NIR-OLEDs.
构建有机近红外（NIR）发光材料以克服“能隙定律”这一巨大障碍仍然具有挑战性。在此，通过将N，N-二苯基萘-2-胺和三苯胺与新型吸电子单元6-（4-（叔丁基）苯基）-6H-吲哚并[2,3-b]喹喔啉-2,3-二甲腈相连，开发了两种名为T-β-IQD和TIQD的近红外热激活延迟荧光（TADF）分子。已证实，具有聚集诱导发光效应的近红外TADF发射体、具有分子内和分子间CN⋅⋅⋅H-C和C-H⋅⋅⋅π相互作用的J-聚集体以及固态下较大的中心间距可提高薄膜和非掺杂有机发光二极管（OLED）中的发光效率。因此，基于T-β-IQD的非掺杂近红外OLED实现了9.44 %的最大外量子效率（EQE），发射峰位于711 nm，这是迄今为止报道的非掺杂近红外OLED的最高效率之一。
