期刊
ADVANCED FUNCTIONAL MATERIALS
卷 30, 期 34, 页码 -出版社
WILEY-V C H VERLAG GMBH
DOI: 10.1002/adfm.202002681
关键词
isomer engineering; organic light-emitting diodes; red emitters; thermally activated delayed fluorescence
类别
资金
- National Key R&D Program of China [2016YFB0401000]
- National Natural Science Foundation of China [21935005, 51803069]
- Program for JLU Science and Technology Innovative Research Team [2019TD-33]
The development of efficient red thermally activated delayed fluorescence (TADF) emitters with an emission wavelength beyond 600 nm remains a great challenge for organic light-emitting diodes (OLEDs). Herein, two pairs of isomers are designed and synthesized by attaching electron-donor 9,9-diphenyl-9,10-dihydroacridine (DPAC) moiety to the different positions of two kinds of highly rigid planar acceptor cores (PDCN and PPDCN). Their TADF efficiencies and emission maxima (599-726 nm) are regulated by molecular isomer manipulation. Interestingly, the photoluminescence quantum yields (phi(PL)s) oftrans-isomers T-DA-1 and T-DA-2 (78% and 89%) are remarkably higher than those of their correspondingcis-isomers C-DA-1 and C-DA-2 (12% and 14%). Significantly increased phi(PL)values can be explained by single crystal structures and theoretical simulation. As a result, a deep red TADF-OLED based on T-DA-2 displays a maximum external quantum efficiency (EQE) of 26.26% at 640 nm. Notably, at a brightness of 100 cd m(-2), the EQE value of T-DA-2-based device still remains at an extremely high level of 23.95%, representing the highest value for reported red TADF-OLEDs at the same brightness. These results provide a reasonable pathway to optimize optoelectronic properties and thereby construct efficient red TADF emitters through rational isomer engineering.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据