高效的近红外辐射受益于减缓内部转换过程的速度
Mingliang Xie1, Yannan Zhou1, Huayi Zhou1
1Key Laboratory of Rubber-Plastics of the Ministry of Education, School of Polymer Science & Engineering, Qingdao University of Science and Technology Qingdao 266042 P. R. China sfxue@qust.edu.cn.
Chemical science
|April 19, 2024
概括
研究人员开发了新的有机发射器TPANZPyPI和TPANZ3PI,在深红和近红外区域实现了高光发光量子产量 (PLQY). 在TPANZPyPI中增加的分子刚性通过抑制非辐射衰变来提高电解发光效率.
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:
- 由于显著的非辐射衰变 (k_nr),开发具有高光发光量子产率 (PLQY) 的有机深红 (DR) 和近红外 (NIR) 发射器具有挑战性.
- 有机发光二极管 (OLED) 中的高效电光发射需要将能量损失路径降到最低.
研究的目的:
- 为DR/NIR应用设计和合成具有高PLQY的新型有机发射剂.
- 研究有机材料中有效发光的结构-属性关系.
- 为了证明分子刚性的潜力,提高激电利用效率 (EUE) 和电光发光.
主要方法:
- 合成了TPANZPyPI和TPANZ3PI有机发射剂.
- 光发光量产量 (PLQY) 的测量.
- 理论计算 (例如,内部换率).
- 非兴奋剂和兴奋剂OLED设备的制造和表征.
主要成果:
- TPANZPyPI膜在699nm时达到46.5%的高PLQY.
- 理论分析显示,TPANZPyPI中S1到S0的内部转换率 (IC) 很小,这有助于高NIR排放PLQY.
- TPANZPyPI的刚性结构抑制了T2到T1的IC过程,提高了激子利用效率 (EUE).
- 使用TPANZPyPI的无添加OLED显示出NIR发射 (4.6%的最大外部量子效率 (EQEmax) @684nm).
- 被杂的OLED显示了DR发射 (6.9%EQEmax @ 666nm),是混合局部电荷转移状态材料>640nm中最高的.
结论:
- 增加的分子刚性有效地抑制了激发状态IC过程,除了S1到S0 IC.
- 这一策略可以在DR/NIR有机发射器中实现高效的电发光.
- 开发的发射器代表了OLED应用程序的重大进步,需要高效的红色和近红外光辐射.
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