暂时移位状态增强有机分子半导体中孔的移动性
Samuele Giannini1, Lucia Di Virgilio2, Marco Bardini3
1Laboratory for Chemistry of Novel Materials, University of Mons, Mons, Belgium. samuele.giannini@umons.ac.be.
Nature materials
|September 14, 2023
概括
有机半导体中的电荷载体具有温度依赖的移动性. DNTT和C8-DNTT-C8之间的移动性差异源于它们的电子带结构影响了电荷转移.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 有机电子 有机电子
背景情况:
- 有机半导体中的电荷载体通常由于动态失调而自我定位.
- 然而,一些有机半导体的移动性会随着温度的升高而降低,这表明带传输已脱局.
研究的目的:
- 为了研究高性能有机半导体中取决于温度的电荷载体移动性:dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]-thiophene (DNTT) 和C8-DNTT-C8.
- 阐明这些相关材料中不同移动行为的微观起源.
主要方法:
- 太赫兹光导度测量以探测电荷载体动力学.
- 原子的非adiabatic分子动力学模拟,以建模电荷传输机制.
主要成果:
- DNTT和C8-DNTT-C8都表现出动力法下降的运动 (μ) 随着温度 (T) 的增加,以下μ T-n.
- 两个半导体之间的指数'n'显著不同.
- 模拟将这些差异归因于热可访问的电荷载体状态的移位,受其电子带结构的支配.
结论:
- 这些有机半导体中的电荷传输涉及在振动上穿着的延伸状态上移动的孔.
- 温度依赖的移动性作为材料密度状态和电荷移位特性的一个敏感指标.
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