在二维碳基材料中对应负热膨胀和热导率
1School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur - 700032, West Bengal, India. spad@iacs.res.in.
Physical chemistry chemical physics : PCCP
|November 25, 2024
概括
本研究探讨了各种二维碳全方位的负热膨胀 (NTE) 和热导率 (TC). 德尔塔-石墨烯表现出最强的NTE和最低的TC,而石墨烯则表现出相反的情况,为材料设计提供了洞察力.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 负热膨胀 (NTE) 是一种反直觉的现象,材料在加热时收缩.
- 了解声子传输特性对于控制二维碳全方位的热导电性 (TC) 是至关重要的.
- 各种二维碳全方位的NTE和TC行为仍然不完全理解.
研究的目的:
- 调查在石墨烯,海克利特,五氧化石,s-石墨烯,6.6.12-石墨烯和三角石墨烯中控制NTE和TC的机制.
- 为了将孔径大小和曲等结构特征与观察到的热特性相关联.
- 阐明语音模式,组速度,寿命和平均自由路径在确定NTE和TC中的作用.
主要方法:
- 使用第一原理计算来分析声传输特性.
- 研究的软声波模式,声波组速度 (vg),声波寿命 (τ) 和平均自由路径 (MFP).
- 检查了外平面曲折和特定孔径对热特性的影响.
主要成果:
- 德尔塔-石墨烯表现出最高的NTE和最低的TC,而石墨烯则表现出相反的情况.
- 石墨烯显示较低的异构性TC,而s-石墨烯显示最高的异构性TC.
- 发现外平面曲折通过增加音声散射来降低TC,但增强NTE.
结论:
- 这项研究加深了对二维碳材料中NTE和TC机制的理解.
- 结构控制,特别是孔径大小和曲,显著影响软单元模式和热特性.
- 这些发现突显了工程碳基的潜力,用于纳米技术和复合材料的应用,这些应用需要定制的热膨胀.
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