基于量子阱结构的高效磷光有机电致发光器件

采用多重量子阱结构制作了高效红色磷光有机电致发光器件。以4,4'-bis(N-carbazolyl)-1,10-biphenyl (CBP)掺杂bis(1-phenyl-isoquinoline)(Acetylacetonato) iridium(Ⅲ) (Ir(piq)₂(acac))为发光层,4,4'-bis(N-carbazolyl)-1,10-biphenyl(Bphen)为电荷控制层,形成了Ⅱ型双量子阱结构,器件的最大亮度为15 000 cd/m²,最大电流效率为7.4 cd/A,相对于参考器件提高了21%。研究结果表明:以Bphen为电荷控制层形成的Ⅱ型多重量子阱结构能有效地将载流子和激子限制在势阱中,并且使空穴和电子的注入更加平衡,从而提高了载流子复合的几率和器件的效率。

High Efficiency Phosphorescent Organic Light-emitting Devices Based on Multiple Quantum Well Structure

High efficiency red phosphorescent organic light-emitting devices were fabricated based on multiple quantum well(MQW) structure.A type-Ⅱ MQW structure is formed by using 4,4′-bis(N-carbazolyl)-1,10-biphenyl(CBP)∶bis(1-phenyl-isoquinoline)(Acetylacetonato) iridium(Ⅲ)(Ir(piq)2(acac)) as the red emitting layer and 4,4′-bis(N-carbazolyl)-1,10-biphenyl(Bphen) as the charge control layer.The MQW device shows a maximum luminescence and current efficiency of 15 000 cd/m2 and 7.4 cd/A,respectively.The current efficiency of the MQW device is enhanced by 21% compared with the reference device.The improvement is attributed to the well confined of the holes and electrons in the MQWs and the balanced charge carrier injection,which results in an increased charge carrier recombination probability and enhances the efficiency.