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在基于n-alkanethiolate的SAM中,负荷运输中的奇偶效应
Mostafa Baghbanzadeh1, Felice C Simeone, Carleen M Bowers
1Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|November 8, 2014
概括
通过自组装单层 (SAM) 进行电荷传输,对黄金电极有奇偶效应,但对银电极没有奇偶效应. 电流密度的这种差异归因于链中碳原子的数量.
科学领域:
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
- 分子电子学分子电子学
背景情况:
- 自组装单层 (SAM) 在分子电子学中对于控制电荷传输至关重要.
- 了解分子结构对电子属性的影响,是设备优化的关键.
研究的目的:
- 研究基链长度平价 (奇数与偶数的碳原子) 对通过SAM传输电荷的影响.
- 为了比较不同金属电极 (金和银) 的这种效应.
主要方法:
- 制造具有结构M(TS) /SAM//Ga2O3/EGaIn (M = Au或Ag) 的分子连接点.
- 在SAM中测量电流密度-电压 (J(V)) 特性.
- 对道电流密度 (J0) 和道衰变常数 (β) 的统计分析.
主要成果:
- 对于金电极上的SAM,观察到对电荷传输具有统计学意义的奇偶效应,但对银的SAM没有.
- 虽然注入电流密度 (J0) 在黄金上的奇数和偶数链长度之间存在差异,但道衰变常数 (β) 仍然无法区分.
- 金和银电极的电气特性相似,表明链倾斜角度对注射电流密度的影响最小.
结论:
- 在n-alkanethiolate SAM中碳原子的数量影响金和银表面的电荷传输不同.
- 观察到的对黄金的奇偶效应表明了与链条平价相关的特定相互作用或包装安排.
- 道衰变常数是一个强大的参数,在本研究中不受链平价或电极材料的影响.
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