直接测量二维共价有机框架的高平面内导热率
Jinghang Dai1, Qiyi Fang2,3, Gustavo A Alvarez1
1Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA.
Nature communications
|July 14, 2025
概括
二维共价有机框架显示高平面内导热率,对于轻量化热管理至关重要. 孔径大小显著影响这些先进材料的热传输.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 热力工程是热力工程中的一个.
背景情况:
- 二维共价有机框架 (2DCOFs) 是先进的多孔材料,具有轻量化热管理的潜力.
- 对于大面积的2DCOF薄膜,缺乏全面的导热数据,特别是在平面内.
- 了解2DCOF中的热传输对于它们在热管理中的应用至关重要.
研究的目的:
- 测量具有不同孔径的大小的2DCOF的内平面和横平面导热率.
- 为了研究毛孔大小对热传输特性的影响.
- 阐明2DCOF中的热传导机制.
主要方法:
- 基于激光的探测技术,包括用于平面内导电的短暂热格子光谱 (TTGS).
- 频域热反射率 (FDTR) 用于横平面导电性.
- 草地事件广角X射线散射 (GIWAXS) 用于结构分析.
主要成果:
- 一个高的1.18±0.21W/m·K的平面内导热率被测量为一个2DCOF与1.4纳米孔径大小.
- 观察到孔径对平面内导热率有显著的影响.
- 在有较大的孔隙的样本中发现了弱热异构性.
结论:
- 直接在平面内测量导热率,为2DCOFs提供关键数据.
- 孔径大小工程是优化2DCOF热传输的关键因素.
- 这些发现支持2DCOFs作为高性能热管理材料的发展.
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