自发定向偏振对三倍三倍向上转换的蓝色有机发光二极管的影响
Shunta Kakumachi1, Hajime Nakanotani1,2, Yuto Nagasaki1
1Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
ACS applied materials & interfaces
|June 6, 2024
概括
有机发光二极管 (OLED) 中的自发方向偏振可能会对性能产生负面影响. 一个极性电子输送层 (ETL) 转移了重组区,降低了三倍三倍上转换 (TTU) 效率和外部量子效率 (EQE).
科学领域:
- 有机电子学有机电子学
- 材料科学是一种材料科学.
- 光物理学的光学物理学
背景情况:
- 自发定向极化 (SOP) 在有机半导体中诱导巨型表面潜力 (GSP),影响有机发光二极管 (OLED) 机制.
- 了解GSP的作用对于优化OLED性能至关重要,特别是在三重三重升级 (TTU) 应用中.
研究的目的:
- 调查由具有正SOP的极电子传输层 (ETL) 诱导的载体重组区迁移如何影响TTU中的OLED性能.
- 量化这种迁移对TTU效率和外部电解发光量子效率 (EQE) 的影响.
主要方法:
- 制造具有极性 (TPBi) 和非极性ETL的OLED设备.
- 分析电流密度依赖的电发光 (EL) 光谱,以确定重组区的转移.
- 在不同的条件下测量TTU效率和EQE.
主要成果:
- 带有极性ETL (TPBi) 的OLED显示TTU效率下降了20%,这是由于减少了三重刺激子密度.
- 外部量子效率 (EQE) 在极地ETL下降到5.4%,在1mA cm-2下降到5.4%,而非极地ETL则为8.1%.
- 电极光谱证实了极极ETL的OLED重组区的电压依赖转移.
结论:
- 由极性ETL驱动的载波重组区的电压依赖迁移,在TTU中显著降低了OLED的性能.
- 在HTL/EML接口附近的固定重组区增强了TTU,而在EML/ETL接口的迁移区减少了三倍激子密度和整体效率.
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