使用分子结构调整因达基基共聚物中的链内和链间电荷传输
Garrett LeCroy1, Raja Ghosh2, Parker Sommerville3
1Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
Journal of the American Chemical Society
|July 26, 2024
概括
高电荷载体转移在聚乙基-共基亚醇中 (p(IDT-BT)) 能够实现高电子传输,与聚乙基-共基 (p(IDT-BPD)) 不同. 这突显了1D转移的效率.
科学领域:
- 材料科学
- 有机电子
- 聚合物化学
背景情况:
- 刚性杆聚合物对于有机电子非常重要.
- 了解充电传输机制是开发高效设备的关键.
- 电荷载体的移动性会受到链内移动的影响.
研究的目的:
- 为了比较两个结构相似的聚合物中的电荷传输,p ((IDT-BT) 和p ((IDT-BPD).
- 研究链内移位对电子传输特性的影响.
- 阐明聚合物结构与电荷载体运动之间的关系.
主要方法:
- 量子化学计算以评估扭转障碍和结合.
- 吸收和光发光谱以确定能量障碍.
- 电荷调制光谱 (CMS) 和电荷载体移位分析的模型计算.
主要成果:
- 比p(IDT-BPD) 具有较低的结合长度和更高的能量障碍.
- 在p ((IDT-BT) 中的电荷载体在很大程度上是分散的,占据了统一的能量环境.
- 导致电荷载体崩和穿越太空的道.
结论:
- 在p ((IDT-BT) 中,电荷载体的高移动性是由于1D链内显著的移位.
- 在设备相关的尺度上实现高移动性是可能的.
- 结构上的差异对有机半导体的电荷传输机制有很大影响.
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