在三色和四色捐赠器-空间器-接受器数组中,分子内能量转移的长度依赖性
Anthony Harriman1, Laura J Mallon, Kristopher J Elliot
1Molecular Photonics Laboratory, School of Chemistry, Bedson Building, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom. anthony.harriman@ncl.ac.uk
Journal of the American Chemical Society
|September 17, 2009
概括
研究人员使用二甲基 (BODIPY) 染料创建了新的捐赠者-接受者分子. 这些分子在不同距离上有效地传输能量,显示了先进太阳能应用的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 摄影化学的使用.
- 超分子化学 超分子化学
背景情况:
- 二甲基 (BODIPY) 染料是具有可调节光学性能的多功能光体.
- 捐赠者-接受者系统对于人工光合作用和光电子学中的能量传输过程至关重要.
- 控制特定距离的电子能量传输 (EET) 是设计功能分子材料的关键.
研究的目的:
- 基于BODIPY染料合成和表征了一系列的捐赠者-空间-接受者三合体.
- 为了研究不同BODIPY单元之间的电子能量传输 (EET) 的距离依赖性.
- 探索分子结构,电子性质和能量传输效率之间的关系.
主要方法:
- 基于BODIPY的不同间距长度 (18-38 Å) 的捐赠器-间距器-接受器三元组的合成.
- 使用光谱技术 (吸收,发射) 和电子电阻测量进行表征.
- 选择性激发单个子单元以研究能量传输路径.
主要成果:
- 在传统和扩展的BODIPY单元之间观察到高效的电子能量传输 (EET).
- EET率显示出对间距长度的非线性但浅度依赖,在20年内仅下降了4倍.
- 发现间隔器电子电阻与与对联长度相关的黄瑞斯因子之间存在相关性.
- 间隔器照明导致EET到两个终端,路径涉及不同的激发状态,取决于分子长度.
- 一个分子四位数证明了从pyrene到BODIPY的快速EET,其次是远程EET.
结论:
- 合成的BODIPY三位一体表现出高效和可调节的远程能量传输.
- EET的浅距离依赖性归因于随着分子长度的增加而减少的能量差距.
- 这些材料由于高效的分子间和分子内部能量转移,显示出它们作为高效的太阳能缩器的前景.
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