在短链 thiazolothiazole-thiophene 共聚物中,高层排序和无形类pi网络导致高流动性
Itaru Osaka1, Rui Zhang, Geneviève Sauvé
1Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Journal of the American Chemical Society
|February 3, 2009
概括
半导体聚合物中的高载体流动性可以在没有长脊柱或晶体侧链的情况下实现. 新的聚乙烯类系统尽管结构混乱,但表现出卓越的电子性能.
科学领域:
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
- 聚合物科学 聚合物科学
背景情况:
- 聚甲基) 是广泛研究的半导体聚合物用于有机电子.
- 载体的移动性对于电子性能至关重要,并且经常通过增加骨干长度或侧链结晶度来增强.
- 之前的研究表明,高晶度和长脊柱是良好的电子性能所必需的.
研究的目的:
- 为了研究基于蒂奥芬的半导体聚合物与 thiazolothiazole 单位 (PTzQT) 的电子性能.
- 为了确定长的结合脊柱和高度晶体的侧链是否对于高载体移动性至关重要.
- 探索材料结构,混乱和电荷传输特性之间的关系.
主要方法:
- 基于烯的半导体聚合物的合成 (PTzQT).
- 测量航母机动性的测量.
- 热分析和X射线散射以评估结晶性和分子包装.
- 原子力显微镜 (AFM) 分析纳米尺度形态.
主要成果:
- PTzQT聚合物表现出较高的载体移动性 (约. 0.3 cm2/Vs) 尽管分子量低且侧链结晶性抑制.
- 材料在纳米尺度上显示出高度混乱的性质,形成无形类型的超结构.
- 载体的移动性随着基侧链的长度而增加,与表面粗性特征相关.
结论:
- 在聚乙烯类系统中,高载体流动性可以在没有长联的脊椎或显著的侧链结晶性的情况下实现.
- 材料混乱和纳米级表面粗度在控制这些系统中的电荷传输方面发挥着至关重要的作用.
- 这些发现挑战了提高有机半导体移动性的传统策略.
相关概念视频
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