Achieving Simultaneously Ultrahigh Brightness, Extremely Low Efficiency Roll-Off and Ultralong Lifetime of Blue Fluorescent OLEDs by Using Donor-Acceptor-Type 5,9-Diarylamine Functionalized Pyrenes

作者：Xie, Fuli; Yang, Xilin; Jin, Pengcheng; Wang, Xiao-Tian; Ran, Huijuan; Zhang, Hailu; Sun, Huaming; Su, Shi-Jian^*; Hu, Jian-Yong^*

来源：Advanced Optical Materials, 2023, 11(4).

DOI：10.1002/adom.202202490

• blue organic light-emitting diodes
• donor-acceptor type fluorescent emitters
• low efficiency roll-off
• pyrene-based blue emitter
• ultrahigh brightness
• ultralong lifetime

In this study, four new donor-acceptor (DA)-type blue emitters (Py(5,9)BDPA, Py(5,9)BMTBA, Py(5,9)BDTBA, and Py (5,9)BTTBA) are developed by adopting benzene ring as A units and the diphenylamine (DPA) with different electron-donating substituents as D units connected to 1,3-positions and 5,9-positions of pyrene ring, respectively. Gratifyingly, single-crystal X-ray analysis of the compounds demonstrates that the disgusting excimers in solid-state could be effectively inhibited by the D units even the unsubstituted DPA resorting to the superiority of introducing D-units at the 5,9-positions of pyrene. The corresponding doped devices display ultrahigh luminance and extremely low efficiency roll-off characteristics, especially for Py(5,9)BDPA, a roll-off of external quantum efficiency is less than 4.9% when the luminance is up to 30 000 cd m(-2), also showing good operation stability of devices. The optimized advanced device of the representative blue emitter Py(5,9)BDPA with a low manufacturing cost achieves extremely long LT95 (lifetime to 95% of the initial luminance) of 74 and 534 h at an initial luminance of 3000 and 1000 cd m(-2), respectively. The ultralong lifetime of the emitter Py(5,9)BDPA is eye-catching in the reported blue OLED lifetime and further demonstrates the practical applications in display and lighting of these DA-type pyrene-based blue emitters.