利用形状动力学来促进电子转移光产品在金属复合体中的形成和捕获
Heather A Meylemans1, Joshua T Hewitt, Mirvat Abdelhaq
1Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, Colorado 80309, USA.
Journal of the American Chemical Society
|August 6, 2010
概括
新的光诱导电子捐赠-接受系统利用硬体体积来控制电荷分离状态. 这种策略通过调整连接体几何和构造动态来增强这些状态的形成和存储.
科学领域:
- 摄影化学的使用.
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 光诱导电子捐赠-接受 (D-A) 系统对于能量转化和储存至关重要.
- 调整DA系统的电子和结构性质是优化其性能的关键.
- 接体设计在控制D-A复合物的行为方面发挥着重要作用.
研究的目的:
- 合成和描述新的光诱导电子捐赠-接受 (D-A) 系统.
- 为了研究固体体积对桥接联体的结构动态的影响.
- 建立一种控制电荷分离状态的形成和存储的战略.
主要方法:
- 合成了三种新的Ru (II) - 双二D-A复合物,它们的硬质量不同.
- 电化学测量以确定电子转移 (DeltaG ((ET)) 和反向电子转移 (DeltaG ((BET)) 的驱动力.
- 时间分辨率光谱 (大约. 100 fs激光脉冲) 来研究光诱导的电子转移动力学.
- 来自模型复合体的发射光谱的弗兰克-康登分析.
主要成果:
- 电子转移 (ET) 和反向电子转移 (BET) 的驱动力在整个系列中是不变的.
- 光诱导的电子转移 (ET) 发生得很快 (29-57 ps),尽管硬质体量增加.
- 电荷分离状态 (tau(BET)) 的寿命显著增加 (高达8倍) 与固体散装 (98-789 ps).
结论:
- 基于连接体的扭动动力学,由连接体内电子移位驱动,促进了快速的ET.
- 在电荷分离状态下的硬体排斥驱动器逆转了形状动力学,增加了寿命.
- 对连接体几何学的立体控制为增强电荷分离状态的形成和储存提供了一种新的策略.
相关概念视频
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