可逆和高对比的导热转换在具有负波桑比率的灵活的共价有机框架中
Sandip Thakur1, Ashutosh Giri1
1Department of Mechanical, Industrial and Systems Engineering, University of Rhode Island, Kingston, RI 02881, USA. ashgiri@uri.edu.
Materials horizons
|October 16, 2023
概括
研究人员开发了一种灵活的共价有机框架,可以实现18倍可逆变化的导热率. 在热传输控制方面的这一突破可以使先进的热开关和二极管成为可能.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 固态物理 固态物理
背景情况:
- 动态控制热传输对于热开关等技术至关重要.
- 现有的对刺激有反应的材料具有有限的热切换比率 (1.5-4x).
研究的目的:
- 为了证明可逆导热性切换具有显著增强的比率.
- 探索灵活的共价有机框架的潜力,以实现先进的热管理.
主要方法:
- 制造一种灵活的共价有机框架 (COF),使用循环胺键.
- 调查框架对外部刺激的反应,如客体吸附/脱附和机械应变.
- 描述热传输特性和波桑比率.
主要成果:
- 在热导率上实现了前所未有的18倍可逆变化.
- 在扩展 (低导电性) 和收缩 (高导电性) 阶段之间证明了框架转换.
- 确定了负波桑比率,表明了辅助性行为.
结论:
- 开发的COF为高性能热开关提供了一个新的平台.
- 材料设计将低密度与卓越的热和机械性能相结合.
- 动态 imine 连接是实现大型可逆热传输调制的关键.
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