Highly efficient single-layer organic light-emitting devices using cationic iridium complex as host
Highly efficient single-layer organic light-emitting devices using cationic iridium complex as host
复制标题
DOI：
10.1016/j.orgel.2012.12.026
复制
发表时间：
2013-03
影响因子：
3.2
通讯作者：
Bing Chen;Yanhu Li;Yueying Chu;Anmin Zheng;Jiwen Feng;Zhitian Liu;Hongbin Wu;Wei Yang
中科院分区：
文献类型：
--
作者：
Bing Chen;Yanhu Li;Yueying Chu;Anmin Zheng;Jiwen Feng;Zhitian Liu;Hongbin Wu;Wei Yang
以窄带隙阳离子Ir配合物[Ir（Meppy）2（pybm）]（PF 6）（C1）为客体，宽带隙阳离子Ir配合物[Ir（dfppy）2（tzpy-cn）]（PF 6）（C2）为主体，制备了以共混阳离子Ir配合物为发光层的高效单层有机电致发光器件.与单一的阳离子Ir配合物发光层相比，这种主-客体体系具有很高的发光效率，最大发光效率为25.7cd/A，外量子效率为8.6%，是纯C1基发光层的近3倍。与含有C1作为发光层和TPBI作为电子传输和空穴阻挡层的多层无主体器件相比，上述单层器件也显示出2倍的增强效率。在这些主体-客体系统中实现的高效率是基于离子Ir络合物的固态发光器件所报道的最高值之一。此外，当C1浓度为0.1wt.%时，还获得了CIE为（0.36，0.47）的类白光发光，发光效率为4.2cd/A。研究结果表明，离子型铱配合物的主客体体系为利用单层器件结构和溶液加工技术实现高效有机发光器件提供了一条新的途径。
Highly efficient single-layer organic light-emitting devices (OLEDs) based on blended cationic Ir complexes as emitting layer have been demonstrated using narrow band gap cationic Ir complex [Ir(Meppy)2(pybm)](PF6) (C1) as guest and wide band gap cationic Ir complex [Ir(dfppy)2(tzpy-cn)](PF6) (C2) as host. As compared with single cationic Ir complex emitting layer, these host–guest systems exhibit highly enhanced efficiencies, with maximum luminous efficiency of 25.7cd/A, external quantum efficiency of 8.6%, which are nearly 3-folds of those of pure C1-based device. Compared with a multilayer host-free device containing C1 as emitting layer and TPBI as electron-transporting and hole-blocking layer, the above single-layer devices also show 2-folds enhancement efficiencies. The high efficiencies achieved in these host–guest systems are among the highest values reported for ionic Ir complexes-based solid-state light-emitting devices. In addition, a white-similar emission with CIE of (0.36, 0.47) has also been achieved with luminous efficiency of 4.2cd/A as the C1 concentration is 0.1wt.%. The results demonstrate that the ionic Ir complexes-based host–guest system provides a new approach to achieve highly efficient OLEDs upon single-layer device structure and solution-processing technique.