一个分子动力学模拟研究双层石墨烯的内平面和横平面导热性
Rafat Mohammadi1, Mohammad Reza Ghaderi1, Ebrahim Hajian2
1Department of Mechanical Engineering, Faculty of Engineering, Arak University, Arak 38156-88349, Iran.
Materials (Basel, Switzerland)
|October 28, 2023
概括
双叶石墨烯 (BLG) 显示出异型导热性,这对于电子学至关重要. 齐格扎格边缘提供比扶手椅边缘更高的内平面导电性,这种导电性随着温度和应变而降低.
科学领域:
- 材料科学 材料科学 材料科学
- 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:
- 高效的热管理对于现代电子设备至关重要.
- 需要具有异性热导电性的薄膜来进行散热和绝缘.
- 双叶石墨烯 (BLG) 是这种应用的一个有前途的材料.
研究的目的:
- 为了研究双层石墨烯 (BLG) 板的导热性.
- 为了检查在平面内和横平面内的导热率.
- 了解温度,应变和边缘类型对BLG热性能的影响.
主要方法:
- 使用了非平衡分子动力学模拟.
- 对不同板长,边缘类型 (齐格扎克和扶手椅),温度和拉伸应变的热导率进行了研究.
- 分析了内平面和横平面导热率.
主要成果:
- 在300 K的10 nm × 10 nm BLG的平面内导热率为~204 W/m·K (zigzag) 和~124 W/m·K (扶手椅).
- 在平面内导电性随板材长度增加而增加,并且在齐克扎克边缘时高出30-40%.
- 温度上升 (300K至600K) 降低了形BLG的平面导电率~34%;12.5%的拉伸应变降低了~51%.
- 在300 K的横平面导热率为~0.05 W/m·K,明显低于平面内值.
- 横平面热导率随着温度的增加而下降,在600K时达到300K值的16%左右.
结论:
- BLG在导热性方面表现出显著的异构性,在平面内比横平面值高得多.
- 与扶手椅边缘的BLG相比,齐格扎克边缘的BLG在飞机内表现出优越的热性能.
- BLG的热导率对温度,应变和边缘配置敏感,提供可调节的热管理可能性.
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