在分子连接处自组装的本佐提-本佐提单层的热电特性
Sergio Gonzalez-Casal1, Rémy Jouclas2, Imane Arbouch3
1Institute for Electronics Microelectronics and Nanotechnology (IEMN), CNRS, Av. Poincaré, Villeneuve d'Ascq 59652, France.
The journal of physical chemistry letters
|November 11, 2024
概括
我们研究了二-二 (BTBT) 分子结的热电特性. C8-BTBT-C8中的链降低了导热,而弱合提高了Seebeck系数,产生了高达10^-4.4的功率 (ZT).
科学领域:
- 分子电子学分子电子学
- 热电能转换热电能转换的方法
- 纳米级的传热方式
背景情况:
- 分子连接提供可调节的热电特性.
- 了解结构与财产的关系是有效收集能源的关键.
研究的目的:
- 调查甲-甲 (BTBT) 和其基化衍生物 (C8-BTBT-C8) 分子连接的热电特性.
- 确定链和电极合对热导率和Seebeck系数的影响.
- 评估这些分子系统的热电功率 (ZT).
主要方法:
- 组合实验技术:导电原子力显微镜 (C-AFM) 和扫描热显微镜 (SThM).
- 使用密度函数理论 (DFT) 进行理论计算.
- 在金基板上使用自组装单层制造分子连接.
主要成果:
- 对C8-BTBT-C8的每分子测量热导电率低至8.8pW/K,归因于链诱导的界面热阻.
- 观察到BTBT的Seebeck系数为36μV/K,C8-BTBT-C8的Seebeck系数为245μV/K,后者是由于核心电极合弱.
- 在300 K的BTBT分子连接处推导出了高达大约10^-4的热电功率 (ZT) 值.
结论:
- 链通过引入界面电阻,显著减少了分子连接处的热传输.
- 在BTBT核心和电极之间的弱电子合增强了Seebeck系数.
- 基于BTBT的分子连接展示了与已建立的系统相比的有希望的热电性能.
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