用于高效红色磷光有机发光二极管的双极性芴基咔唑基主体材料

Bipolar Fluorenylcarbazole-based Host Materials for Efficient Red Phosphorescent Organic Light-emitting Diodes

为提高有机发光二极管的发光效率,设计合成了两种新的红光磷光双极性主体材料FC-CZ-PQZ和FC-BCz-PQZ,两种材料均表现出优秀的光物理性能、较高热稳定能力和平衡的载流子传输能力,FC-BCz-PQZ表现最佳,与FC-Cz-PQZ相比,FC-BCz-PQZ的热稳定能力更强、载流子传输平衡性更好。以FC-CZ-PQZ和FC-BCz-PQZ为主体,制备了红色PhOLEDs,FC-BCz-PQZ表现出了较高的电致发光性能,电流效率、功率效率和最大外量子效率分别为13.5 cd/A、14.2 lm/W和14.8%,说明FC-BCz-PQZ有潜力成为红光PhOLED主体材料。

Achieving high-efficiency red phosphorescent organic light-emitting diodes(PhOLEDs)is still a challenge,which is largely related to the host material used in device fabrication.Two new bipolar hosts,2-(9 H-carbazol-9-yl)-7,7-dimethyl-5-(4-phenylquinazolin-2-yl)-5,7-dihydroindeno[2,1-b]carbazole(FC-CZ-PQZ)and 2-(4-(9 H-carbazol-9-yl)phenyl)-7,7-dimethyl-5-(4-phenylquinazolin-2-yl)-5,7-dihydroindeno[2,1-b]carbazole(FC-BCz-PQZ),were designed and synthesised as host materials to fabricate red PhOLEDs.The two compounds exhibited excellent physical properties with high thermal stabilities and balanced charge transport.FC-BCz-PQZ has a better bipolar carrier transport compared to FC-CZ-PQZ.FC-BCz-PQZ-based device demonstrated good electroluminescence performance with the maximum current efficiency,power efficiency and external quantum efficiency of 13.5 cd/A,14.2 lm/W and 14.8%,respectively,suggesting its promising application as a host material for red PhOLEDs.