在刚性合的四二聚体中增强NIR-到可见的上转换:使用分子内多激励状态接近三倍三倍灭绝的统计极限
Alexander T Gilligan1, Raythe Owens1, Ethan G Miller1
1Department of Chemistry, University of Colorado Boulder Boulder Colorado 80309 USA niels.damrauer@colorado.edu.
Chemical science
|January 26, 2024
概括
光子上升转换将近红外光转换为可见光. 一种新的共价二元体,TIPS-BTX,通过优化三倍三倍的消灭途径,显示了比其单元体TIPS-Tc高出20倍的上转换产量.
科学领域:
- 摄影化学的使用.
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
背景情况:
- 光子上升转换对于将近红外光子转换为可见光至关重要,可用于各种领域.
- 目前的上转效率,特别是在近红外区域,往往落后于可见光谱中的效率.
- 三倍三倍灭绝 (TTA) 是光子向上转换的关键机制,但其效率高度依赖于分子设计.
研究的目的:
- 为了研究一个形状定义的共价二极体,TIPS-BTX,对于光子上转换的潜在好处.
- 系统地比较TIPS-BTX的上转换性能与一个相关的单体,TIPS-四烯 (TIPS-Tc).
- 为了阐明底层光物理过程,负责任何观察到的上升转换效率差异.
主要方法:
- 对共价二聚体TIPS-BTX和单聚体TIPS-Tc.的合成和表征.
- 光物理研究包括吸收,发射和时间分辨率光谱学.
- 在可比条件下量化确定上转换量子收益率 (φ_UC) 和三倍三倍消灭 (TTA) 效率.
- 对旋转统计因素的分析,以了解刺激子的动态.
主要成果:
- 在同样的条件下,TIPS-BTX的上转换收益率 (φ_UC) 超过TIPS-Tc的20倍 (0.16%).
- 提升TIPS-BTX的φ_UC仅归因于TTA过程,其有效收益率是TIPS-Tc的30倍以上.
- TIPS-BTX的旋转统计系数 (f = 0.42) 相当于领先的消灭器系统,这表明它能有效地进入生产道.
结论:
- 与其单体对应物相比,像TIPS-BTX这样的形态定义的共价二极体可以显著提高光子上转换效率.
- 优化三倍三倍的消灭途径和最大限度地减少非生产性道对于开发高性能升级转换系统至关重要.
- 结果表明,分子内多激励状态和受控的自旋动力学在高效的光子上转换中起着至关重要的作用.
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