• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Advanced Functional Materials >Influence of Cavity Thickness and Emitter Orientation on the Efficiency Roll-Off of Phosphorescent Organic Light-Emitting Diodes
【24h】

Influence of Cavity Thickness and Emitter Orientation on the Efficiency Roll-Off of Phosphorescent Organic Light-Emitting Diodes

机译：腔体厚度和发射极取向对磷光有机发光二极管效率衰减的影响

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

This article describes the first systematic investigation of how the efficiency roll-off in organic light-emitting diodes (OLEDs) is influenced by the position and orientation of the emitter molecules within the OLED cavity. The efficiency roll-off is investigated for two OLED stacks containing either the phosphorescent emitter lr(MDQ)_2(acac) or lr(ppy)_3 by varying the distance between emitter and metal cathode; a strong influence of emitter position and orientation on roll-off is observed. The measurements are modeled by triplet-triplet-annihilation (TTA) theory yielding the critical current density and the TTA rate constant. It is found that lr(MDQ)_2(acac) shows the lowest roll-off when the emitter is located in the first optical maximum of the electromagnetic field, whereas the roll-off of the lr(ppy)_3 stack is lowest when the emitter is positioned closer to the metal cathode. Measurement and modeling of time-resolved electroluminescence show that the different roll-off behavior is due to the different orientation and the corresponding change of the decay rate of the emissive dipoles of lr(MDQ)_2(acac) and lr(ppy)_3. Finally, design principles are developed for optimal high-brightness performance by modeling the roll-off as a function of emitter-cathode distance, emissive dipole orientation, and radiative efficiency.
机译：本文介绍了有关有机发光二极管（OLED）的效率下降如何受到OLED腔内发射器分子的位置和方向的影响的首次系统研究。通过改变发射极和金属阴极之间的距离，研究了两个包含磷光发射极lr（MDQ）_2（acac）或lr（ppy）_3的OLED堆叠的效率下降。观察到发射器位置和方向对滚降的强烈影响。通过三重态-三重态an灭（TTA）理论对测量进行建模，得出临界电流密度和TTA速率常数。发现当发射极位于电磁场的第一光学最大值时，lr（MDQ）_2（acac）的滑降最低，而当发射极位于电磁场的第一光学最大值时，lr（ppy）_3叠层的滑降最低。发射极靠近金属阴极。时间分辨电致发光的测量和建模表明，不同的滚降行为是由于lr（MDQ）_2（acac）和lr（ppy）_3的发射偶极子的方向不同和相应的衰减率变化引起的。最后，通过将衰减模拟为发射极-阴极距离，发射偶极子定向和辐射效率的函数，开发出了最佳高亮度性能的设计原理。

著录项

  • 来源
    《Advanced Functional Materials》 |2014年第8期|1117-1124|共8页
  • 作者

    Caroline Murawski; Philipp Liehm; Karl Leo; Malte C. Gather;

  • 作者单位

    Institut fuer Angewandte Photophysik Technische Universitaet Dresden George-Baehr-Str. 1, 01062, Dresden, Germany;

    Institut fuer Angewandte Photophysik Technische Universitaet Dresden George-Baehr-Str. 1, 01062, Dresden, Germany;

    Institut fuer Angewandte Photophysik Technische Universitaet Dresden George-Baehr-Str. 1, 01062, Dresden, Germany;

    Institut fuer Angewandte Photophysik Technische Universitaet Dresden George-Baehr-Str. 1, 01062, Dresden, Germany,SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号