具有悬浮五基的聚合物中的持久多 excitons
Lauren M Yablon1, Samuel N Sanders1, Hua Li2
1Department of Chemistry , Columbia University , New York , New York 10027 , United States.
Journal of the American Chemical Society
|May 24, 2019
概括
这项研究探讨了聚合物链中的单片裂变,通过穿越空间的相互作用实现了高效的激子乘法. 这种新型的五聚合物产生了长寿的三胞胎,
科学领域:
- 有机光伏产品
- 材料科学
- 摄影化学
背景情况:
- 单子裂变 (SF) 是有机物质中一个关键的激子乘法过程,将一个单子激子转化为两个三重激子.
- 传统的SF研究侧重于晶体膜或分离的分子二极体.
- 一种涉及聚合物链中穿越空间相互作用的中间模式仍未得到充分探索.
研究的目的:
- 在隔离的聚合物链中研究单片裂变和三片对重组.
- 探索如何将五色素添加到多聚基骨干会影响SF效率和三重体动力学.
- 确定这些聚合物系统能否产生长寿的三胞胎.
主要方法:
- 聚合物的合成与悬挂的五烯单元连接到一个多聚烯骨干.
- 对光物理过程的光谱检测,包括单粒裂变和三粒灭.
- 分析分子动力学及其对SF和三重复合动力学的影响.
- 在溶液和薄膜状态下测量三重激素寿命.
主要成果:
- 具有悬浮五基的宏分子表现出通过空间 π-π 相互作用调解的高效单片裂变.
- 三倍重组被确定为双结合过程,重组率取决于聚合物分子量.
- 与传统的晶体染色体相比,合成的悬浮聚合物表现出优越的自由三重体寿命.
结论:
- 悬浮五聚合物为利用穿越空间的相互作用提供了一个有前途的平台,以实现高效的单片裂变.
- 这些聚合物提供了一个可行的途径来产生长寿命的三重激子,超过了晶体类型的性能.
- 这些发现为设计用于能源转化应用的先进有机材料开辟了新的途径.
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