A deep blue fluorescent emitter of 4′, 4‴-(1H-phenanthro [9, 10-d]-imidazole-1, 2-diyl) bis (N, N-diphenyl-[1,1′-biphenyl]-4-amine) (PPI-2TPA) possessing special virtues of high triplet energy, excellent photoluminescence quantum yield and preferable bipolar transporting property was employed as host material by the first time to realize a highly efficient phosphorescent organic light-emitting device (OLED). In comparison with the reference device, the optimized device had better performance, which showed the maximum efficiencies of 40.4 cd/A and 45.3 l m/W and still kept high efficiencies of 39.7 cd/A and 37.1 l m/W at the luminance of 1000 cd/m². Moreover, the critical current density was as high as 179.6 mA/cm², which was about 1.8-fold that of the reference device, indicating a significant alleviation of efficiency drop at high current density in the optimized device. The emission of phosphorescent emitter originated from both energy transfer and hole-electron recombination, distinctly revealed by a systematical analysis on the device electroluminescence (EL) characteristics. Simultaneously, an efficient hybrid white OLED as well as a tandem white OLED which demonstrated quite slight color variation over a wide range of luminance were also constructed.

4'，4′-（1H-菲咯[9，10-d]-咪唑-1，2-二基）双（N，N-二苯基-[1,1'-联苯] -4）的深蓝色荧光发射体具有高三重态能量，优异的光致发光量子产率和优选的双极传输性质的优点的P-胺（PPI-2TPA）被首次用作主体材料，以实现高效的磷光有机发光器件（OLED）。与参考器件相比，优化后的器件具有更好的性能，其最大效率为40.4 cd / A和45.3 lm / W，并且在1000 cd的亮度下仍保持了39.7 cd / A和37.1 lm / W的高效率。 / m ²。此外，临界电流密度高达179.6 mA / cm ²，约为参考器件的1.8倍，这表明优化器件在高电流密度下的效率下降得到了显着缓解。通过对器件电致发光（EL）特性的系统分析清楚地揭示了磷光发射体的发射源于能量转移和空穴-电子复合。同时，还构建了在宽广的亮度范围内表现出很小的颜色变化的有效的混合白色OLED以及串联式白色OLED。