Li Zhe, Yang Dezhi, Han Chunmiao, Zhao Bingjie, Wang Huiqin, Man Yi, Ma Peng, Chang Peng, Ma Dongge, Xu Hui
Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, 150080, P. R. China.
Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640, P. R. China.
Angew Chem Int Ed Engl. 2021 Jun 25;60(27):14846-14851. doi: 10.1002/anie.202103070. Epub 2021 May 24.
Herein, we report a deep-red TADF emitter pCNQ-TPA, composed of quinoxaline-5,8-dicarbonitrile (pCNQ) acceptor and triphenylamine (TPA) donor. pCNQ-TPA supported its OLED with desired CIE coordinates of (0.69, 0.31) and the record maximum external quantum efficiency of 30.3 %, which is the best red TADF diode with Rec.2020 gamut for UHDTV. It is showed that through tuning pCNQ-TPA doping concentration, intra- and inter-molecular charge transfer are balanced to synchronously improve emission color saturation and TADF radiation, and remedy aggregation-induced quenching, rendering photoluminescence quantum yield (PLQY) reaching 90 % for deep-red emission peaked at ≈690 nm. Quasi-planar structure further endows pCNQ-TPA with an improved horizontal ratio of emitting dipole orientation, which increases light out-coupling ratio to 0.34 for achieving the state-of-the-art device efficiencies.
在此，我们报道了一种深红色热激活延迟荧光（TADF）发光体pCNQ-TPA，它由喹喔啉-5,8-二甲腈（pCNQ）受体和三苯胺（TPA）供体组成。pCNQ-TPA所支撑的有机发光二极管（OLED）具有所需的CIE坐标（0.69, 0.31）以及创纪录的30.3%的最大外量子效率，这是用于超高清电视（UHDTV）的具有Rec.2020色域的最佳红色TADF二极管。结果表明，通过调节pCNQ-TPA的掺杂浓度，分子内和分子间的电荷转移得以平衡，从而同步提高发射颜色饱和度和TADF辐射，并弥补聚集诱导猝灭，使得在≈690 nm处达到峰值的深红色发射的光致发光量子产率（PLQY）达到90%。准平面结构进一步赋予pCNQ-TPA更高的发射偶极子取向水平比，将光出射耦合比提高到0.34，以实现最先进的器件效率。
