Double-layer and triple-layer organic light-emitting diodes (OLEDs) were fabricated using a novel star-shaped hexafluorenylbenzene organic material, 1, 2, 3, 4, 5, 6-hexakis (9,9-diethyl-9H-fluoren-2-yl) benzene (HKEthFLYPh) as an energy transfer layer, N,N'-bis-(1-naphthyl)-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (NPB) as a hole-transport layer (HTL) and blue emissive layer (EML), and tris (8-hydroxyquinoline) aluminum (Alq3) as an electron-transport layer (ETL) and green light-emitting layer. Bright white light was obtained with a triple-layer device structure of indium-tin-oxide (ITO)/NPB(40nm)/HKEthFLYPh(10nm)/Alq3(50nm)/Mg:Ag(200nm). A maximum luminance of 8523cd·m-2 at 15 V and a power efficiency of 1.0 lm·W-1 at 5.5V were achieved. The Commissions Internationale de L' Eclairage (CIE) coordinates of the device were (0.29, 0.34) at 9 V, which located in white light region. With increasing film thickness of HKEthFLYPh, light emission intensity from NPB increased compared to that of Alq3.%使用星形六苯芴类新材料1,2,3,4,5,6-hexakis(9,9-diethyl-9H-fluoren-2-y1)benzene(HKEthFLYPh)分别制备了三种不同结构的有机电致发光器件.在结构为indium-tin oxide(ITO)/NPB(40nm)/HKEthFLYPh(10nm)/Alq3(50nm)/Mg:Ag(200nm)的器件中,获得了两个电致发光谱峰分别位于435和530nm处的明亮白光.HKEthFLYPh足能量传输层;N,N'-bis-(1-naphthyl)-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine(NPB)是空穴传输层和蓝色发光层;tris(8-hydroxyquinoline)aluminum(Alq3)是电子传输层和绿色发光层.结果表明,当驱动电压为15V时,器件的最大亮度达到8523cd·m-2;在5.5V时,器件达到最大流明效率为1.01m·W-1.在电压为9V时,CIE色坐标为(0.29,0.34).此外,通过改变HKEthFLYPh层的厚度,发现蓝色发射的相对强度随着HKEthFLYPh层厚度的增加而增强.
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