具有本征手性光学性质的还原联萘吩恶嗪热激活延迟荧光分子的设计合成及其在圆偏振有机发光二极管的应用

Axially chiral biphenoxazine-based thermally activated delayed fluorescence materials for solution-processed circularly polarized organic light-emitting diodes

Lang Qu, Hui Xiao Bao Zhang, Qingping Yang, Jintong Song, Xiangge Zhou, Zong-Xiang Xu*, and Haifeng Xiang*

Chem. Eng. J. 2023, DOI: 10.1016/j.cej.2023.144709

Circularly polarized organic light-emitting diodes (CP-OLEDs) from pure organic thermally activated delayed fluorescence (TADF) materials are a research hotspot due to their low price and high electroluminescence efficiency for antiglare filters and 3D displays. Herein, one pair of intrinsically chiral octahydro-binaphthalenes-based biphenoxazine dyes were designed, prepared, and characterized. Bearing one axially chiral electron-donor (D) biphenoxazine core and two electron-acceptor (A) 2,4,6-triphenyl-s-triazineine fragments, they are tri-propeller-type, which would be in favour of both charge separation and A-D-D-A charge transfer to achieve aggregation-induced yellow-green TADF with a quantum yield of 25.2% and 57.6% for neat and doped film, respectively. Most importantly, they can be acted as emitters in solution processed CP-OLEDs to achieve luminance, current efficiency, external quantum efficiency, and dissymmetry factor up to 1.66 × 10⁴ cd m^-2, 35.2 cd A^-1, 11.3% and 0.88 ×10^-3, respectively. Moreover, the dissymmetry factor can be further enhanced to 1.69 ×10^-3, if semitransparent electrodes are adopted.