在新Bodipy衍生品中进行激进增强的系统间交叉,并用于高效的三倍-三倍消灭升级
Zhijia Wang1, Jianzhang Zhao1, Antonio Barbon2
1State Key Laboratory of Fine Chemicals, Dalian University of Technology , E-208 West Campus, 2 Ling-Gong Road, Dalian 116024, People's Republic of China.
Journal of the American Chemical Society
|May 20, 2017
概括
研究人员使用激素增强型系统间交叉 (EISC) 在二甲基 (Bodipy) 中实现了长寿命的三重激发状态. 这一突破使得效率高的三倍灭绝转换成为可能,开辟了光化学的新途径.
科学领域:
- 摄影化学
- 有机化学
- 光谱学
背景情况:
- 二甲基 (Bodipy) 是一个众所周知的化物.
- 三重激发状态在光物理过程中至关重要.
- 激进增强型系统间交叉 (EISC) 提供了三重状态的途径.
研究的目的:
- 首次观察和描述长寿三胞胎的激发状态.
- 在Bodipy-nitroxide二中研究EISC的机制.
- 探索EISC在三倍三倍灭绝 (TTA) 上转换中的应用.
主要方法:
- 具有不同链接长度的Bodipy-TEMPO二极管的合成.
- 稳定状态和时间分辨率的瞬态光学光谱.
- 连续波电子自旋共振 (cw-ESR) 和时间解析ESR (TR-ESR).
主要成果:
- 使用较短的链接器实现了有效的EISC (ΦT=80%) 和长时间的Bodipy三重状态寿命 (62μs).
- TR-ESR通过激素三重对机制确认了自旋偏振的TEMPO信号.
- 在TTA上转化中成功使用了EISC,量子收益率为6.7%.
结论:
- 在灵活的Bodipy-nitroxide系统中证明了有效的EISC和长的三倍寿命.
- 这与之前在刚性EISC系统中的发现形成鲜明对比.
- 该研究展示了EISC在TTA升级应用中的潜力.
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