在以碳为基础的分子结合中,光刺激近共振电荷传输超过60纳米
Shailendra K Saxena1, Ushula M Tefashe1, Richard L McCreery1
1Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada.
Journal of the American Chemical Society
|August 14, 2020
概括
在分子连接处的光诱导电流是比暗电流高的数量级, 揭示了先进分子电子学的新运输机制.
科学领域:
- 分子电子
- 有机电子产品
- 材料科学
背景情况:
- 了解分子结合中的电荷传输机制对于开发先进的电子设备至关重要.
- 基于碳的分子结合为电子应用提供了独特的特性.
- 这些结点的电流的厚度和温度依赖是需要研究的关键参数.
研究的目的:
- 调查基于碳的分子结合中的黑暗和光诱导电流的偏差和温度依赖.
- 通过一系列的寡合层厚度来阐明酸分子结合中的电荷传输机制.
- 将光诱导电流与暗电流的行为进行比较.
主要方法:
- 碳基分子连接的制造和特征与不同的寡合层厚度 (460nm).
- 测量黑暗和光诱导电流的电流密度与偏差 (JV) 和温度依赖性.
- 与电场和厚度相关的电流行为分析.
主要成果:
- 暗流显示了薄层的指数厚度依赖 (<5 nm) 和较厚层的弱依赖 (1560 nm).
- 光诱导电流明显高于暗电流,并表现出不同的偏差依赖性.
- 黑暗和光诱导电流在厚度>14 nm时变得依赖电场,在200 K以下显示无激活行为.
结论:
- 轨道介导的传输,涉及分子轨道之间的连续道,被建议用于光诱导的电流.
- 暗电流受到界面能量屏障的限制,而光诱导电流则受到大量限制.
- 这些发现表明,快速,低阻碍的运输可以将分子电子的操作范围扩展到50纳米之外.
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