工程热传输穿过长轴格子-不匹配的范德瓦尔斯异质接口
Emigdio Chavez-Angel1, Polychronis Tsipas2, Peng Xiao1
1Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, Barcelona 08193, Spain.
Nano letters
|July 19, 2023
概括
工程 2D 材料创造了具有超低导热率的高绝缘热元材料. 与天然材料相比,这些人工材料提供了优越的热管理特性.
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:
- 人工设计的二维材料具有独特的热性能,可用于先进的热管理.
- 范德瓦尔斯的表能够创建具有可调性特征的新型异构结构.
研究的目的:
- 使用二维材料设计和表征极具绝热性的热元材料.
- 研究这些工程材料中影响横平面散热的因素.
主要方法:
- 范德瓦尔斯表达式用于制造Bi2Se3/MoSe2超和石墨烯/PdSe2异构结构.
- 频域热反射和低频拉曼光谱用于测量热性质.
- 严密结合的声计算用于理论分析.
主要成果:
- 在室温下实现了特殊的热电阻 (70-202 m2 K/GW) 和超低的横平面导热率 (0.012-0.07 W/mK).
- 证明了格子不匹配,音频接口散射,尺寸效应和温度显著影响散热.
- 确定了长波长声子在横平面热传输中的主导作用.
结论:
- 工程 2D 范德瓦尔斯异构结构可以实现无形类型的隔热.
- 了解接口效应对于设计具有量身定制的热传输材料至关重要.
- 为热管理应用开发大面积异质表皮膜提供指导.
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