光子学报, 2018, 47 (12): 1223001, 网络出版: 2019-01-10
以B3PyPPM为电子传输层制备蓝色磷光OLED器件
Fabricating Blue Phosphorescent Organic Light-emitting Devices by Using B3PyPPM as Electron Transport Layer
有机半导体 有机电致发光器件 外量子效率 微腔效应 n掺杂 Organic semiconductor Organic light-emitting device External quantum efficiency Microcavity effect n-doping
摘要
以B3PyPPM作为电子传输层, 分别以TCTA和mCP为母体, 制备A、B两组结构为ITO/HATCN(5 nm)/TAPC(45 nm)/TCTA∶FIrpic(15%,15 nm)/B3PyPPM(X nm)/B3PyPPM∶Cs(15%,10 nm)/Al, ITO/HATCN(5 nm)/TAPC(45 nm)/mCP(5 nm)/mCP∶FIrpic(15%,15 nm)/B3PyPPM(X nm)/B3PyPPM∶Cs(15%,10 nm)/Al的蓝色磷光器件, 其中X的值分别为40 nm、45 nm、50 nm、55 nm.实验证明, mCP作为母体的器件最大亮度和最大电流效率分别达到14 930 cd/m2、9.9 cd/A, 亮度从500 cd/m2上升到3 000 cd/m2时, 外量子效率滚降仅仅只有10.1%, 远优于以TCTA为母体器件的效率滚降特性, 由于B3PyMPM能够改善电子的注入特性, 两组器件的开启电压分别为2.3 V和2.8 V, 低于采用其他电子传输层材料制备的Firpic蓝色磷光器件.在30 mA/cm2电流密度下, 器件光谱有一个波长在474 nm的主峰和496 nm的振动峰, 随着电子传输层厚度的增加, 振动峰的强度增强, 这是由微腔效应引起的, 通过光学模拟详细地研究了器件中存在的微腔现象.
Abstract
We fabricated blue phosphorescent organic light-emitting devices of A and B groups by using B3PyPPM as electron transport layer and TCTA and mCP as host. The structure are: ITO/HATCN(5 nm)/TAPC(45 nm)/TCTA∶FIrpic(15%,15 nm)/B3PyPPM(X nm)/B3PyPPM∶Cs(15%,10 nm)/Al and ITO/HATCN(5 nm)/TAPC(45 nm)/mCP(5 nm)/mCP∶FIrpic(15%,15 nm)/B3PyPPM(X nm)/B3PyPPM∶Cs(15%,10 nm)/Al. The values of X are 40 nm, 45 nm, 50 nm, and 55 nm, respectively. Experiments show that the devices which use mCP as host is far better than the device using TCTA as host. The maximum luminance of 14 930 cd/m2 and the maximum current efficiency of 9.9 cd/A are obtained. The efficiency roll-off in EQE is only 10.1% when the luminance rises from 500 cd/m2 to 3 000 cd/m2. Since B3PyMPM can improve the injection characteristics of electrons, the turn-on voltage of the two groups devices are 2.3 V and 2.8 V, respectively, which is lower than the Firpic blue phosphorescent OLEDs fabricated with other electron transport layer materials. At the current density of 30 mA/cm2, the spectra of all devices have a major peaks at 474 nm and a vibrational peak at 496 nm. As the thickness of B3PyPPM increases, the intensity of the shoulder increases due to the microcavity effect. The microcavity phenomenon existing in the device is studied in detail by optical simulation.
林雯嫣, 喻叶, 彭雪康, 金玉, 吴志军, 刘菁华. 以B3PyPPM为电子传输层制备蓝色磷光OLED器件[J]. 光子学报, 2018, 47(12): 1223001. LIN Wen-yan, YU Ye, PENG Xue-kang, JIN Yu, WU Zhi-jun, LIU Jing-hua. Fabricating Blue Phosphorescent Organic Light-emitting Devices by Using B3PyPPM as Electron Transport Layer[J]. ACTA PHOTONICA SINICA, 2018, 47(12): 1223001.