Wang Liding, Zhao Zifeng, Zhan Ge, Fang Huayi, Yang Hannan, Huang Tianyu, Zhang Yuewei, Jiang Nan, Duan Lian, Liu Zhiwei, Bian Zuqiang, Lu Zhenghong, Huang Chunhui
Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory of Rare Earth Materials Chemistry and Applications, Beijing Engineering Technology Research Centre of Active Display, College of Chemistry and Molecular Engineering, Peking University, 100871 Beijing, China.
Tianjin Key Lab for Rare Earth Materials and Applications, School of Materials Science and Engineering, Nankai University, 300350 Tianjin, China.
Light Sci Appl. 2020 Sep 8;9:157. doi: 10.1038/s41377-020-00395-4. eCollection 2020.
Compared to red and green organic light-emitting diodes (OLEDs), blue OLEDs are still the bottleneck due to the lack of efficient emitters with simultaneous high exciton utilization efficiency (EUE) and short excited-state lifetime. Different from the fluorescence, phosphorescence, thermally activated delayed fluorescence (TADF), and organic radical materials traditionally used in OLEDs, we demonstrate herein a new type of emitter, cerium(III) complex with spin-allowed and parity-allowed - transition of the centre Ce ion. The compound exhibits a high EUE up to 100% in OLEDs and a short excited-state lifetime of 42 ns, which is considerably faster than that achieved in efficient phosphorescence and TADF emitters. The optimized OLEDs show an average maximum external quantum efficiency (EQE) of 12.4% and Commission Internationale de L'Eclairage (CIE) coordinates of (0.146, 0.078).
与红色和绿色有机发光二极管（OLED）相比，蓝色OLED仍然是瓶颈，因为缺乏同时具有高激子利用效率（EUE）和短激发态寿命的高效发光体。与传统用于OLED的荧光、磷光、热激活延迟荧光（TADF）和有机自由基材料不同，我们在此展示了一种新型发光体，即具有中心Ce离子自旋允许和宇称允许跃迁的铈（III）配合物。该化合物在OLED中表现出高达100%的高EUE和42 ns的短激发态寿命，这比高效磷光和TADF发光体的激发态寿命快得多。优化后的OLED显示平均最大外量子效率（EQE）为12.4%，国际照明委员会（CIE）坐标为（0.146, 0.078）。
