与四个受体分子共价连接的电子供体单晶中的长寿命电荷分离
Jeremy M Fisher1, Malik L Williams1, Jonathan R Palmer1
1Department of Chemistry and Paula M. Trienens Institute for Sustainability and Energy, Northwestern University, Evanston Illinois 60208-3113, United States.
Journal of the American Chemical Society
|March 26, 2024
概括
具有共价连接的供体-受体分子形成晶体,有效地产生和维持太阳能电荷载体. 这一突破使得电荷分离的寿命长, 对于推进太阳能转换技术至关重要.
科学领域:
- 材料科学
- 太阳能发电
- 有机电子
背景情况:
- 晶体捐赠-接受 (D-A) 系统是理解太阳能转换中的激子动态的关键.
- 由于强大的电子合和D-A单元的近距离,现有的D-A共晶面临电荷分离寿命的限制.
- 协价D-A系统提供了预先组织结构和设计晶体形态的策略,以改善电荷分离.
研究的目的:
- 在新型共价D-A单晶中研究光生成的电荷转移 (CT) 激子的形成.
- 分析PerPh4-NDI分子的晶体结构和包装图案.
- 评估工程D-A晶体结构中的电荷分离的效率和寿命.
主要方法:
- 一个共价的捐赠体-接受体分子PerPh4-NDI的合成,其中包括一个四烯捐赠体和四个纳二二氧化接受体.
- 用X射线结晶学来确定PerPh4-NDI单晶体的固态结构和包装安排.
- 超快速光谱技术探测电荷转移激子形成和测量电荷载体寿命.
主要成果:
- 在PerPh4-NDI晶体结构中,X射线晶体学揭示了NDI受体的两个不同的包装图案.
- 选择性光刺激的PerPh4供体导致快速电荷转移 (CT) 激子在不到300 femtosecond的时间内形成.
- 产生的电子孔对具有超过大约16微秒的异常长寿命.
结论:
- 联D-A系统有效地设计了促进高效和长寿命的电荷分离的晶体结构.
- 单晶PerPh4-NDI显示出一个有前途的平台来推进太阳能转换.
- 这项工作突显了在有机固体中定制分子设计的潜力,以优化光伏性能.
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