用BPhen作基质的铕配合物OLED发光机制研究

Emission mechanism in europium-complex organic electroluminescent devices using BPhen as host

用具有良好电子传输/空穴阻挡性能的BPhen(4,7-diphenyl-1,10-phenanthroline)作基质,Eu(DBM)3pyzphen(pyzphen=pyrazino-[2,3-f][1,10]-phenanthroline,DBM=Dibenzoylmethane)作发射材料,成功制得了高效率、高亮度的有机电致发光器件OLED。器件的最大外量子效率为2.5%,最大电流效率为5.3cd/A,最大亮度为1320cd/m2。在亮度为200和1000cd/m2时,器件的色坐标分别为(0.66,0.33)和(0.65,0.34)。深入研究了该器件的发光机制,发现在电致发光(EL)过程中,载流子直接被Eu(DBM)3pyzphen陷获是主要的发光机制,同时在BPhen与Eu(DBM)3pyzphen间还存在着有效的能量传递。

High efficiency pure red organic electroluminescent deviees（OLED） were fabricated by doping Eu（DBM）3 pyzphen into electron transporting/hole blocking material Bphen as emission layer. A maximum current efficiency of 5.3 cd/A,an external quantum efficiency of 2.5% and a maximum luminance of 1 320 cd/m^2 were obtained from the optimal device. The color coordinates were （0, 66,0.33） and （0.65,0.34） at the brightness of 200 and 1000 cd/m^2 ,respectively. The emission mechanism in the device was investigated in detail. Energy transfer and carrier trapping simultaneously exist in the electroluminescence process,and carrier trapping is a main process.