新型高色纯度弱电流猝灭性蓝色有机发光器件

以ADN为基质,分别以不同掺杂剂制备了四种蓝色有机发光器件,器件结构为:CuPc(12 nm)/NPB(40 nm)/AND∶Dopant(50 nm)/Alq(12 nm)/LiF(4 nm)/Al。掺杂剂有:BCzVB(amino-substituted distyrylarylenederivatives)、TBPe、BCzVBi和DSA-ph四种。研究了最佳掺杂浓度以及器件的亮度、电流密度、效率和色坐标等电学特性和光学特性。其中掺杂BCzVB制备了色纯度高、低电流猝灭性的蓝色有机发光器件,色坐标达到x=0.146,y=0.162,最大亮度为11600 cd/m2(15 V),电流效率为2.8 cd/A,流明效率为1.79 lm/W;以ADN为基质,分别以TBPe、BCzVBi和DSA-ph为掺杂剂,制备了另外三种对比器件。器件ADN∶TBPe色坐标为x=0.162,y=0.222(蓝绿光),效率随电流的增加而降低很快;器件ADN∶BczVBi有较好的色纯度(色坐标:x=0.164,y=0.146),但电流效率较低:2.03 cd/A,效率随电流的增加降低幅度也较快。器件ADN∶DSA-ph效率较高为8 cd/A,效率随电流增加变化幅度不大,但色纯度比较差(x=0.153,y=0.306),适合于做白色有机发光器件。

Novel Blue Organic Light Emitting Diode with Highly Saturated Color and Weak Current-Induced Quenching

Four blue organic light emitting diodes (OLED) based on anthracene derivatives( ADN) doped with different dopants have been prepared. The device structure is CuPc(12 nm)/NPB(40 nm)/ADN∶Dopant(50 nm)/Alq(12 nm)/LiF(4 nm)/Al. The four dopants are amino-substituted distyrylarylene derivatives(BCzVB), tetra-butylperylene (TBPe), BCzVBi and DSA-ph. The optium concentration of dopants, the luminescence, current density, efficiency and color coordinates of these devices are explored. The device based on ADN doped with BCzVB shows high color purity and a weak current-induced fluorescence quenching. With CIE coordinates x=0.146,y=0.162, maximum luminance 11600 cd/m2 (15 V), current efficiency 2.8 cd/A, and luminous efficiency 1.79 lm/W. For comparison, the blue OLEDs based on ADN doped with TBPe BCzVBi and DSA-ph are also made. The first exhibits CIE coordinates x=0.162, y=0.222 (greenish blue) and a steep decline of efficiency with the increase of the current. The second gives a better purity (x=0.164,y=0.146) but lower current steeply declining with increase of current efficiency 2.03 cd/A. The last has high efficiency 8 cd/A and a weak current-induced fluorescence quenching, but poor CIE coordinates x=0.153，y=0.306, and it is suitable for white OLED.