Constructing Highly Efficient Blue OLEDs with EQE up to 7.5% Based on Anthracene Derivatives

Chemistry. 2021 Sep 23. doi: 10.1002/chem.202103012. Online ahead of print.ABSTRACTAcquiring desirable device performance with deep-blue color purity that fulfills practical application requirements is still a challenge. Bipolar fluorescent emitters with HLCT state may serve to address this issue. Herein, by inserting anthracene core in the deep-blue building blocks, we successfully developed two highly twisted D-π-A fluorescent emitters, ICz-An-PPI and IP-An-PPI , featuring different acceptor groups. Both exhibited superb thermal stabilities, high PLQYs and excellent bipolar transport capabilities. The non-doped OLEDs using ICz-An-PPI and IP-An-PPI as the emitting layers showed efficient blue emission with an EQE max of 4.32% and 5.41%, and the CIE coordinates of (0.147, 0.180) and (0.149, 0.150), respectively. In addition, the deep blue doped device based on ICz-An-PPI was achieved with an excellent CE max of 5.83 cd A -1 , EQE max of 4.6% and the CIE coordinate of (0.148, 0.078), which is extremely close to the National Television Standards Committee (NTSC) standard. Particularly, IP-An-PPI -based doped device had better performance, with an EQE max of 7.51% and the CIE coordinate of (0.150, 0.118), which was very impressive among the recently reported deep-blue OLEDs with the CIE y ＜ 0.12. Such high performance may be attributed to the hot exciton HLCT mechanism via T 7 to S 2 . Our work may provide a new approach for designing high-efficiency deep-blue materials.PMID:...

Source: Chemistry - September 23, 2021 Category: Chemistry Authors: Xu-Hui Zheng Ting-Ting Huang Guo-Xi Yang An-Qi Lin Keng Chen Xiang Chen Jiu-Yan Li Qing-Xiao Tong Source Type: research