聚合聚合物薄膜中电荷导电的极化依赖性用时间分辨率特拉赫兹光谱学研究
Timothy J Magnanelli1, Sebastian Engmann1,2, Jared K Wahlstrand1
1Physical, Measurement Laboratories, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USA.
概括
时域特拉赫兹 (TDS) 光谱学揭示了半导体聚合物中的电荷传输. PCDTPT显示方向导电性,为优化电子应用提供载体动力学和材料性能的见解.
科学领域:
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
- 频谱学是一种光谱学.
背景情况:
- 半导体聚合物对于有机电子产品至关重要.
- 了解电荷传输是设备性能的关键.
- 时域特拉赫兹 (TDS) 光谱学提供非接触方法来探测电荷动态.
研究的目的:
- 通过使用TDS和时间解析特拉赫兹 (TRTS) 来研究薄膜半导体聚合物的载体移动性和电荷生成效率.
- 分析不同形态的PCDTPT共聚合物薄膜中的电荷导电.
- 为了比较PCDTPT中的电荷动态与聚-3-基 (P3HT).
主要方法:
- 利用了室温时间域特拉赫兹 (TDS) 和时间分辨率特拉赫兹 (TRTS) 光谱.
- 采用THz偏振异性质探头来研究电荷导电.
- 对比了PCDTPT的对齐薄膜,滴薄膜和液体分散.
- 对比结果与短暂吸收数据和P3HT.
主要成果:
- 在PCDTPT中,由于极化异构,观察到沿脊柱方向的偏电导电.
- 发现薄膜形态和处理显著影响方向移动性和电荷对产量.
- 在烯分散中的PCDTPT表现出意想不到的高导电性.
- 获得了对极子/自由电荷放松和转移机制的定量见解.
结论:
- THz极化异质性是理解导向聚合物薄膜中的电荷传输的强大工具.
- 在PCDTPT中,材料处理和形态学对电荷载体动力学产生了重大影响.
- 这项研究增强了对不同聚合物形态中的电荷载体运动,扩散和放松的理解.
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