New bipolar host materials with the different number of benzo[f]quinoline and carbazole groups were synthesized for green phosphorescent organic light-emitting diodes (PHOLEDs). We controlled the number of the electron transporting benzo[f]quinoline moieties and the hole transporting carbazole moieties to adjust charge balance at the emitting layer (EML) with those bipolar host materials. In addition, we found that they give relatively high triplet energy level (T₁ > 2.50 eV) which is suitable for green host materials. As a result, the green PHOLEDs employing those materials together with bis(2-phenylpyridine)(acetylacetonato) iridium (III) [Ir(ppy)₂(acac)] as a dopant showed moderately high current efficiency up to 42.85 cd/A.

合成了具有不同数量的苯并[f]喹啉和咔唑基团的新型双极主体材料，用于绿色磷光有机发光二极管（PHOLED）。我们控制了电子传输苯并[f]喹啉部分和空穴传输咔唑部分的数目，以调节那些双极性主体材料在发射层（EML）的电荷平衡。此外，我们发现它们具有较高的三线态能级（T ₁  > 2.50 eV），适用于绿色主体材料。结果，将那些材料与双（2-苯基吡啶）（乙酰丙酮基）铱（III）[Ir（ppy）₂（acac）]一起用作掺杂剂的绿色PHOLED显示出中等高的电流效率，最高可达42.85 cd / A。