基于Cyclopenta[b]thiopyran的角形异构体的晶体工程用于控制电荷载体的移动性
Yanjun Qiao1, Longfei Yang1, Jiangyu Zhu1
1Department of Materials Science, Fudan University, Shanghai 200433, China.
Journal of the American Chemical Society
|July 16, 2021
概括
基于环[b]thiopyran的有机半导体被合成. 修改链并添加原子改善了电场效应晶体管中的分子包装和电荷载体移动性.
科学领域:
- 有机电子产品
- 材料科学
- 半导体物理
背景情况:
- 环[b]二烯是[b]二烯的同位素,与青具有同电子性.
- 有机半导体对于开发诸如场效应晶体管 (FET) 等先进电子设备至关重要.
- 可溶性有机半导体需要精心的分子设计才能达到最佳性能.
研究的目的:
- 合成基于环[b]thiopyran的新型角形异构.
- 研究链长度和替代对这些异质的特性的影响.
- 在有机场效应晶体管 (OFET) 中关联分子结构,晶体包装和电荷传输特性.
主要方法:
- 合成两个系列的环[b]衍生物:C-SS (不同的链长度) 和C-SS-Cl (不同的替代位置).
- 光物理和电化学性质的表征,包括近红外吸收和最高占用分子轨道 (HOMO) 能量水平.
- 使用单晶X射线衍射分析分子包装结构.
- 在场效应晶体管中测量电荷载体的移动性.
主要成果:
- 已经成功合成了7种S-异质,具有相似的光物理和电化学特性.
- 尽管具有相同的π结合骨架,但分子包装结构显著影响了电荷载体的移动性.
- 在中等链长度下,C-SS系列的最大孔移动性为1.1 cm2/V·s.
- 加入原子缩短了分子间S·H接触和平面间的距离.
- 结晶溶剂影响了晶体包装;从中结晶的C-SS-Cl的最大孔移动性为2.7cm2/V·s.
结论:
- 原子的引入是调晶体结构和有机半导体中的电荷传输的可行策略.
- 悬挂链和化位置的分子工程是优化OFET中电荷载体移动性的关键.
- 这项研究强调了分子间相互作用和晶体包装在确定有机电子材料性能方面的关键作用.
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