基于激基复合物主体的高效杂化白光有机发光二极管  

High Efficiency Hybrid White Organic Light-emitting Diodes Based on Exciplex Host

作　　者：边浩冬 李佳睿 张春芳 冯旗 郝一泓 陈金辉 薛蕊 李登峰 柳渊 BIAN Haodong;LI Jiarui;ZHANG Chunfang;FENG Qi;HAO Yihong;CHEN Jinhui;XUE Rui;LI Dengfeng;LIU Yuan(School of Instrument Science and Opto-Electronics Engineering,Beijing Information Science and Technology University,Beijing 100192,China)

机构地区：[1]北京信息科技大学仪器科学与光电工程学院,北京100192

出　　处：《发光学报》2024年第7期1163-1172,共10页Chinese Journal of Luminescence

基　　金：国家自然科学基金(62105039);北京市教育委员会科技计划项目(KM202211232015);中国科学技术协会托举人才项目(YESS20200146);北京信息科技大学校基金资助项目(2121YJPY208)。

摘　　要：在有机发光二极管(OLEDs)中,发光层中载流子的平衡以及激子分布区域的拓宽对于提高器件效率是至关重要的。本研究采用SiCzCz∶SiTrzCz2激基复合物(Exciplex)主体设计制备了基于热激活延迟荧光(TADF)材料DMAC-DPS和TDBA-SAF的低效率滚降蓝光发光器件,并以相同Exciplex为主体材料,通过引入红光磷光材料RD071和绿光磷光材料Ir(ppy)2(acac)构建了同一主体的三层发光结构,实现了高显色指数杂化白光OLEDs的设计。SiCzCz∶SiTrzCz2激基复合物作为主体材料不仅拓宽了激子分布区域,平衡了发光层中载流子传输,并通过与TADF/磷光发光材料三线态能级匹配,构建了级联式激子能量传递途径,从而有效地提高了激子利用率、降低了器件的效率滚降。通过优化器件结构,白光OLEDs实现了最高外量子效率(EQE)、电流效率(CE)、功率效率(PE)分别为23.0%、45.9 cd·A^(-1)和33.9 lm·W^(-1),器件具有较高的显色指数(CRI=87)、良好的光谱稳定性和低的效率滚降。本研究为高显色指数、低效率滚降的杂化TADF/磷光白光器件提供了一种新的设计方案。In organic light-emitting diodes(OLEDs),the balance of carriers in the light-emitting layer and the broadening of the exciton distribution region are crucial for improving device efficiency.In this study,low-efficiency roll-off blue light-emitting devices based on thermally activated delayed fluorescence(TADF)materials DMAC-DPS and TDBA-SAF were fabricated by using exciplex host material SiCzCz∶SiTrzCz2.With the same host material,three-emitting-layer structure was constructed by introducing red phosphorescent emitter RD071 and green phospho⁃rescent emitter Ir(ppy)2(acac),realizing a high color rendering index.The exciplex host material SiCzCz∶SiTrzCz2 not only broadens the exciton distribution region and improves the charge balance,but also constructs a cascaded ex⁃citon energy transfer route by aligning the triplet energies of TADF/phosphorescent emitter materials.Subsequently,the white OLEDs(WOLEDs)effectively improve the exciton utilization and reduce the efficiency roll-off.By optimiz⁃ing the device structure,WOLEDs achieved the highest external quantum efficiency,current efficiency and power efficiency of 23. 0%, 45. 9 cd·A−1 and 33. 9 lm·W−1, respectively. Also, the device has a high color rendering index of 87, good color stability and low efficiency roll-off. This study provides a new design scheme for hybrid white light-emitting devices with high color rendering index and low efficiency roll-off.

关 键 词：有机发光二极管 热激活延迟荧光 激基复合物 载流子平衡 激子传递 

分 类 号：TN312.8[电子电信—物理电子学]