Zhang Tianyou, Zhao Bo, Chu Bei, Li Wenlian, Su Zisheng, Yan Xingwu, Liu Chengyuan, Wu Hairuo, Gao Yuan, Jin Fangming, Hou Fuhua
1] State Key Laboratory of Luminescence and application, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, 3888-Dong NanHu Road, Changchun 130033, P. R. China [2] Graduate School of the Chinese Academy of Sciences, Beijing 100039, P.R. China.
State Key Laboratory of Luminescence and application, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, 3888-Dong NanHu Road, Changchun 130033, P. R. China.
Sci Rep. 2015 May 15;5:10234. doi: 10.1038/srep10234.
Exciplex is well known as a charge transfer state formed between electron-donating and electron-accepting molecules. However, exciplex based organic light emitting diodes (OLED) often performed low efficiencies relative to pure phosphorescent OLED and could hardly be used to construct white OLED (WOLED). In this work, a new mechanism is developed to realize efficient WOLED with extremely simple structure by redistributing the energy of triplet exciplex to both singlet exciplex and the orange dopant. The micro process of energy transfer could be directly examined by detailed photoluminescence decay measurement and time resolved photoluminescence analysis. This strategy overcomes the low reverse intersystem crossing efficiency of blue exciplex and complicated device structure of traditional WOLED, enables us to achieve efficient hybrid WOLEDs. Based on this mechanism, we have successfully constructed both exciplex-fluorescence and exciplex-phosphorescence hybrid WOLEDs with remarkable efficiencies.
激基复合物是一种在供电子分子和吸电子分子之间形成的电荷转移态，这是广为人知的。然而，基于激基复合物的有机发光二极管（OLED）相对于纯磷光OLED而言，效率往往较低，并且很难用于构建白色OLED（WOLED）。在这项工作中，我们开发了一种新机制，通过将三重态激基复合物的能量重新分配给单重态激基复合物和橙色掺杂剂，以极其简单的结构实现高效的WOLED。能量转移的微观过程可以通过详细的光致发光衰减测量和时间分辨光致发光分析直接进行研究。该策略克服了蓝色激基复合物反向系间窜越效率低以及传统WOLED器件结构复杂的问题，使我们能够实现高效的混合WOLED。基于这一机制，我们成功构建了具有显著效率的激基复合物-荧光和激基复合物-磷光混合WOLED。
