高三次能量树枝:增强深蓝色光化 (III) 复合物的发光
Shih-Chun Lo1, Ruth E Harding, Christopher P Shipley
1Centre for Organic Photonics & Electronics, The University of Queensland, School of Chemistry & Molecular Biosciences, QLD 4072, Australia.
Journal of the American Chemical Society
|November 19, 2009
概括
这项研究开发了一种新型的蓝色光 dendrimer,用于高效的光发射. 封装一个复合核心与刚性树枝显著提高光发光量子产量 (PLQY) 显示应用程序.
科学领域:
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
- 光物理学的光学物理学
背景情况:
- 解决方案可加工的蓝色光发射器对于先进的显示器和照明至关重要.
- 优化发射器的物理和光物理性能是提高设备性能的关键.
- (III) 复合物是有前途的光材料,但经常遭受聚合引起的火.
研究的目的:
- 为了增强蓝色光发射器的性能,通过封装一个 (III) 复合核心与刚性,高三重能量.
- 为了研究登德罗化对光发光量产 (PLQY),热稳定性和固态发光量的影响.
- 为了评估在有机发光二极管 (OLED) 中产生的树突体的性能.
主要方法:
- 通过融合方法合成蓝色光树脂体,其中包括一个factor-tris[1-methyl-5-(4-fluorophenyl) -3-n-propyl-1H-[1,2,4]triazolyl]iridium(III) 核心.
- 树突体的物理性质的表征,包括玻璃过渡温度 (Tg) 和溶液可加工性.
- 光物理测量以确定溶液和膜PLQY,以及单层和双层OLED设备中的电光发光.
主要成果:
- 合成的树突体表现出高溶液PLQY (94%),与母核 (27%) 相比显著增加.
- 树突体表现出极好的热稳定性,高Tg为148°C和受控的分子间相互作用,达到60%的膜PLQY.
- 单层OLED显示出0.4%的外部量子效率 (EQE),而双层设备达到3.9%的EQE,受到三重火的限制.
结论:
- 登德罗化是一种有效的策略,可以增强光发射器的光物理性质和可加工性.
- 刚性,高三次能量的树枝成功地抑制了发光灭,从而改善了固态发射.
- 需要进一步优化,以克服双层OLED中的三重火机制,以提高效率.
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