五角形和六角形阵列中的超分子氨酸二极体组件,具有采光天线功能
Fatin Hajjaj1, Zin Seok Yoon, Min-Chul Yoon
1Graduate School of Materials Science, Nara Institute of Science and Technology, Takayama 8916-5, Ikoma, Nara 630-0192, Japan.
Journal of the American Chemical Society
|April 6, 2006
概括
合成的氨酸宏循环模仿采光天线,显示增加的光和更快的能量转移与更多的组件. 具有最佳双极合的六角阵列表现出优越的激发能量跳跃时间.
科学领域:
- 超分子化学 超分子化学
- 摄影化学的使用
- 材料科学 材料科学 材料科学
背景情况:
- 光合成采光天线 (LH) 有效地捕获和传输能量.
- 用合成系统模仿LH天线对于开发人工光合作用和光电子设备至关重要.
- 氨酸宏循环提供了一个多功能平台,用于构建具有可调节光物理性质的有序数组.
研究的目的:
- 合成基于氨酸的新型超分子宏循环阵列作为人工光采集天线.
- 研究宏观周期大小和几何学对光物理性质的影响,包括光量子产量和寿命.
- 确定这些合成天线内的激发能量跳跃 (EEH) 动态及其对结构因素的依赖.
主要方法:
- 使用互补的协调化学合成pentameric (EP5) 和hexameric (EP6) 的宏循环氨酸阵列.
- 使用质子核磁共振和质谱学进行非共振连接 (N-EP5,N-EP6) 和共振连接 (C-EP5,C-EP6) 氨酸阵列的表征.
- 测量光量子产量和寿命.
- 通过exciton-exciton消灭和异性异性去极化研究来确定激发能量跳跃时间.
主要成果:
- 成功合成和特征化了共价连接的宏循环C-EP5和C-EP6.
- 与较小的类似物相比,C-EP5 (10.1%) 和C-EP6 (11.0%) 的光量子产量显著增强,超过二次体C-EP1 (9.3%) 的产量.
- 激发能量跳跃时间被确定为C-EP5的21 ps和C-EP6的12.8 ps,由于改进过渡双极合,在六角阵列中观察到更快的转移.
结论:
- 基于氨酸的宏循环阵列有效地模仿了自然光采集系统.
- 在宏循环中增加氨酸单元的数量可以提高光量子产量,并加速能量转移.
- 宏观循环阵列中的几何排列和过渡双极方向极大地影响了激发能量跳跃的效率.
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