Breakthrough in Efficiency of Exciplex Organic Light-Emitting Diodes Using 9-Phenylfluorene Based Electron Acceptors
Exciplex-thermally activated delayed fluorescence (exciplex-TADF) system is an excellent candidate for fabrication of high-efficiency organic light-emitting diodes (OLEDs) because of its more easily achieved small singlet–triplet energy splitting (Δ E ST ) and doping-control. However, exciplex-TADF is still faced with problems of low external quantum efficiency ( η ext ) and unclear effect of the structure-modification in electron acceptors. Herein, we provide a steric hindrance-increase strategy to obtain high-efficiency exciplex-emissions. Through introducing steric hindrance group (9-phenylfluorene) into N -ethylcarbazole of the dicyano-substituted 9-phenylfluorene, more noticeable electron–hole separation is obtained in the resultant acceptor-based exciplex system, which helps the exciplex harvest smaller Δ E ST , larger driving force and higher emission efficiencies. Encouragingly, the corresponding OLED displays a maximum η ext of 25.8%, which is one of the best efficiency values among reported exciplex-OLEDs, simultaneously possessing excellent current efficiency of 83.6 cd A –1 and power efficiency of 93.7 lm W –1 . It is expected that this work will offer a new avenue for designing electron acceptors for highly efficient exciplex-emissions
Year of publication: |
[2022]
|
---|---|
Authors: | Cao, Hong-Tao ; Yu, Wen-Jing ; Gao, Ying ; Hou, Peng-Fei ; Li, Bo ; Feng, Quan-You ; Zhang, He ; Su, Zhongmin ; Xie, Ling-Hai |
Publisher: |
[S.l.] : SSRN |
Saved in:
freely available
Saved in favorites
Similar items by person
-
Research on the Magneto-Optical Properties of Tb3+-Ho3+ Co-Doped Gbpz Faraday Glass
Lin, Hai, (2022)
-
Predicting the changes in the structure of food demand in China
Zheng, Zhihao, (2018)
-
PPP application in infrastructure development in China : institutional analysis and implications
Zhang, Shuibo, (2015)
- More ...