摘要
制备结构为ITO/HAT-CN/TAPC/TCTA/POAPF\:PO-01/Bphen/LiF/Al的黄色磷光器件,其效率滚降特性符合三重态-极化子淬灭模型;接着设计了一组单电子和单空穴器件,实验结果表明:发光层内的空穴是多子且PO-01俘获空穴,被PO-01俘获的多余空穴引起的激子淬灭是导致器件在高电流密度下效率剧烈滚降的原因;采用N掺杂的方法增加电子注入,可减少发光区内多余的空穴,改善器件载流子的平衡状况,降低多余空穴引起的激子淬灭,进而改善效率滚降。
Yellow phosphorescent organic light-emitting device is prepared, and the structure of the device is ITO/HAT-CN/TAPC/TCTA/POAPF\:PO-01/Bphen/LiF/Al. The efficiency roll-off of the device fits the triplet-polaron quenching model well. Then, electron-only and hole-only devices are designed. Experimental results show that the holes are majority carriers in light-emitting layer and PO-01 traps holes. The efficiency of the device rolls off drastically due to excitons quenching caused by PO-01 trapping excess holes at high current density. The method of N-doping is used to increase the electron injection, which reduces excess holes in the light-emitting region, improves the carriers balance of the device, and alleviates the excitons quenching caused by excess holes, thereby improving the efficiency roll-off.
引文
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