载体-载体排斥限制了无N的有机半导体的导电性
Xuwen Yang1, Gang Ye2, Jian Liu3
1Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 3, Groningen, 9747 AG, The Netherlands.
Advanced materials (Deerfield Beach, Fla.)
|September 9, 2024
概括
分子兴奋剂增强有机半导体的导电性,但高兴奋剂可以减少它. 这项研究揭示了电子对电子排斥,而不是形态学,在n型有机半导体中在高兴奋剂水平下限制导电性.
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:
- 分子兴奋剂对于改善有机半导体导电性至关重要.
- 通常,导电性达到峰值,然后随着兴奋剂度的增加而下降,通常归因于形态变化.
- 最近的模拟表明,电子对电子排斥可能会在高兴奋剂水平下限制导电性.
研究的目的:
- 在高兴剂水平下实验性研究n型有机半导体中限制电导率的因素.
- 要确定电子对电子排斥或形态变化是否是导电率下降的主要原因.
- 为了验证关于载体-载体相互作用作用的模拟预测.
主要方法:
- 测量电导率和Seebeck系数作为n型有机半导体中兴奋剂度的函数.
- 使用金属绝缘体半导体二极管来准确确定载体密度.
- 分析Seebeck系数对载体密度的依赖,以测试海克公式.
主要成果:
- 实验数据证实,在高载体密度下,Seebeck系数遵循Heike公式.
- 这种对海克公式的坚持表明,载体-载体排斥限制了导电性,而不是形态效应.
- 这些发现挑战了有机半导体中电荷传输的现有模型.
结论:
- 与常见的假设相反,载体-载体排斥是限制 doped 有机半导体导电性的重要因素.
- 目前在有机半导体中跳转运输的模型可能需要修订,以纳入这些发现.
- 这项研究为设计高性能有机电子材料提供了新的见解.
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