By introducing pyridine, benzimidazole and triazine groups, three novel CBP derivatives host materials, 9,9'-(2-(pyridin-3-yl)-[1,1′-biphenyl]-4,4′-diyl)bis(9H-carbazole) (CBPPY), 9,9'-(4''-(1- phenyl-1H-benzo[d]imidazol-2-yl)-[1,1':2′,1″-terphenyl]-4,4′-diyl)bis(9H-carbazole) (CBPBM) and 9,9'-(3''-(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1':2′,1″-terphenyl]-4,4′-diyl)Bis (9H-carbazole) (CBPTZ) were designed and synthesized. These three compounds exhibited high thermal stabilities, appropriate HOMO-LUMO energy levels and improved electroluminescent (EL) performance compared with CBP compound in Ir(ppy)₃ doped green organic light emitting diodes (OLED). In addition, devices based on CBPPY, CBPBM and CBPTZ showed lower driving voltages of 3.0, 2.6 and 2.5 V, and all devices achieved higher EL efficiencies. Especially, the CBPBM-based device reached the optimal external quantum efficiencies (EQE) of 18.9% with the maximum power efficiency (PE) of 56.7 l m/W, which suggested that CBPPY, CBPBM and CBPTZ were promising bipolar host materials for green OLEDs.

通过引入吡啶，苯并咪唑和三嗪基团，三种新颖的CBP衍生物可作为主体材料9,9'-（2-（吡啶-3-基）-[1,1'-联苯] -4,4'-二基）双（ 9 H-咔唑）（CBPPY），9,9'-（4''-（1-苯基-1 H-苯并[ d ]咪唑-2-基）-[1,1'：2'，1''-三[苯基] -4,4'-二基）双（9 H-咔唑）（CBPBM）和9,9'-（3''-（4,6-二苯基-1,3,5-三嗪-2-基）设计并合成了-[[1,1'：2'，1''-三联苯基] -4,4'-二基）双（9 H-咔唑）（CBPTZ）。与Ir（ppy）_3中的CBP化合物相比，这三种化合物表现出高的热稳定性，适当的HOMO-LUMO能级和改善的电致发光（EL）性能。掺杂的绿色有机发光二极管（OLED）。此外，基于CBPPY，CBPBM和CBPTZ的器件显示出较低的3.0、2.6和2.5 V驱动电压，并且所有器件均实现了更高的EL效率。尤其是，基于CBPBM的器件达到了18.9％的最佳外部量子效率（EQE），最大功率效率（PE）为56.7 l m / W，这表明CBPPY，CBPBM和CBPTZ是绿色OLED的有希望的双极性主体材料。