在分子连接处的热电.
Pramod Reddy1, Sung-Yeon Jang, Rachel A Segalman
1Applied Science and Technology Program, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|February 17, 2007
概括
研究人员测量了分子连接的热电性质. 他们在金分子金系统中发现了p型导电,为分子热电能转换打开了大门.
科学领域:
- 分子电子学分子电子学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术纳米技术
背景情况:
- 热电材料将热量转化为电力.
- 分子连接提供可调节的电子特性.
- 了解分子系统中的电荷传输至关重要.
研究的目的:
- 测量分子连接的西贝克系数.
- 为了确定金分子金异质连接中的电荷载体类型.
- 探索分子热电能转换的潜力.
主要方法:
- 在黄金电极之间捕获分子 (BDT,二乙醇,三乙醇).
- 在电极上应用温度差异.
- 在室温下测量结点Seebeck系数.
主要成果:
- 测量到的西贝克系数是:+8.7μV/K (BDT),+12.9μV/K (4,4'-二二甲醇),+14.2μV/K (4,4'-三二甲醇).
- 积极的西贝克系数表示明确的p型 (孔) 导电.
- 奥费米水平确定在BDT最高占成的分子轨道上方1.2 eV.
结论:
- 分子连接处表现出显著的热电效应.
- 在金分子金系统中证明了p型导电.
- 突出了分子热电能收集和电子结构研究的潜力.
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