在Ag,Au和Pt接触之间,基于π-结合的基烯和基的分子道连接点:表面连接组和金属加工功能的影响
BongSoo Kim1, Seong Ho Choi, X-Y Zhu
1Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|October 25, 2011
概括
我们使用酸分子研究了分子结点. 我们发现接触类型显著影响阻力,而分子长度决定了道衰减,为电子运输提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 物理化学 物理化学
背景情况:
- 了解分子连接处的电子运输对于开发分子电子学至关重要.
- 奥利戈亚提供了一个可调节的分子骨干,用于研究电荷传输特性.
- 金属分子接触对连接电阻和电子结构的影响需要详细研究.
研究的目的:
- 测量和关联金属分子金属结的道阻力和电子结构.
- 为了研究分子长度和接触类型对接口特性的影响.
- 为了阐明控制基基分子结合中的电荷传输的机制.
主要方法:
- 在金属基板上使用橄烯自组装单层 (SAM) 制造纳米道连接点.
- 使用导探头原子力显微镜 (CP-AFM) 测量连接电阻.
- 使用紫外线光电子谱学 (UPS) 确定电子结构.
主要成果:
- 连接阻力随着分子长度呈指数增长,而道衰减因子 (β) 则取决于金属分子接触的数量.
- 与单醇相比,dithiols的接触电阻 (R(0) 显著较低,并且随着接触工作功能的增加而下降.
- 道衰减因子 (β) 是独立于接触工作功能的,而过渡电压 (V(trans)) 与电子桥梁屏障相关.
结论:
- 化学接触的数量强烈地影响了连接阻力,而分子长度则决定了道衰减.
- 介面键二极管和电子结构在确定分子连接点的传输性质方面发挥着关键作用.
- 一个三重屏障模型有效地解释了观察到的长度和工作函数依赖的运输行为在oligoacene分子连接处.
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