Low efficiency roll-off phosphorescent organic light-emitting devices using thermally activated delayed fluorescence hosts materials based 1, 2, 4-triazole acceptor
作者:Huixia Xu、Yaping Zhao、Jing Zhang、Di Zhang、Yanqin Miao、Joseph Shinar、Ruth Shinar、Hua Wang、Bingshe Xu
DOI:10.1016/j.orgel.2019.06.041
日期:2019.11
The host in phosphrescent organic light emitting devices (PhOLEDs), showing the thermally activated delayed fluorescence (TADF) charateristic, can effectively overcome the efficiency roll-off. Herein, six bipolar compounds with donor-π-acceptor (D-π-A) and D-π-A-π-D structures have been synthesized using 1,2,4-triazole derivative (TAZ) as an acceptor and phenothiazine (PTZ), phenoxazine (PXZ), and
磷光有机发光器件(PhOLED)中的主体具有热激活延迟荧光(TADF)特征,可以有效克服效率下降的问题。在此,使用1,2,4-三唑衍生物(TAZ)作为受体和吩噻嗪( PTZ),吩恶嗪(PXZ)和9、9-二甲基ac啶(DMAC)作为供体。分子结构通过1 H NMR,13 C NMR和X射线单晶衍射确认。大的位阻使这些分子具有典型的TADF特征,包括小的单重态-三重态能量分裂(ΔE小号Ť)为0.08–0.30 eV,并且在空间上完全分开了最大占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)电子密度。这些新颖的TADF材料承载的PhOLED具有出色的性能和低效率的滚降。