针对载流子在面式-三(2-苯基吡啶基-N,C2′)铱(Ⅲ) (Ir(ppy)3)上的聚集会对器件性能产生不良影响, 在发光层中分别掺入4% 的双(2-(4,6-二氟苯基)吡啶基-N,C2′)铱(Ⅲ) (吡啶-2-羧基)配合物 (FIrpic) 和4% 的4,4′,4″-三(咔唑-9-基)三苯胺 (TCTA), 器件的性能有明显的提高, 最高电流效率分别达到51 cd/A和43.1 cd/A, 提高约79%和50%, 我们将器件效率的提高归因于TCTA和FIrpic可以使聚集在Ir(ppy)3界面的空穴向主体材料4,4′-二(咔唑-9-基)联苯 (CBP) 转移, 进而可减弱对激子的猝灭作用。

We present a simple efficient green phosphorescent device based on the direct charge-recombination mechanism in heavy doping Ir(ppy)3. The 4,4′,4″-Tris(carbazol-9-yl)triphenylamine (TCTA) and bis (4,6-difluorophenyl-pyridine)(picolinate) iridium(Ⅲ) (FIrpic) are selected as doping materials that doped into emitting layer respectively. The maximum current efficiency values of 43.1 cd/A and 51 cd/A are demonstrated in these devices, which increased by 50% and 79%, respectively. The results reveal a practical way to fabricate highly efficient bilayer organic devices.