嵌入在室温热管理碳框架中的n-基的巨大的反弹性热量效应
Fangbiao Li1, Xiong Xu1, Guangwei Zhai1
1School of Physics, Hunan Key Laboratory of Super Microstructure and Ultrafast Process, Hunan Key Laboratory of Nanophotonics and Devices, State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China. huiwang@csu.edu.cn.
Nanoscale
|January 31, 2025
概括
研究人员预测,在新型复合材料中,巨大的反弹性热量效应可以用于高效的固态制冷. 这些材料为传统冷却技术提供了一个有希望的,环保的替代方案.
科学领域:
- 材料科学 材料科学 材料科学
- 热力学是一种热力学.
- 固态物理 固态物理
背景情况:
- 固态制冷是蒸汽压缩系统的一个有希望的替代方案.
- 现有的材料面临着诸如低潜热,高驱动力,热歇斯底里斯和低导热等局限性.
- 需要新的材料来实现高效和实用的固态冷却.
研究的目的:
- 在复合和碳纳米管/石墨烯架构中预测巨大的逆弹性热效应 (eCE).
- 评估这些材料在室温固态制冷中的潜力.
- 用eCE为设计无形聚合物提供见解.
主要方法:
- 用分子动力学模拟来研究材料的行为.
- 用热力学分析量化了弹性热量特性.
- 模拟集中在压力压力下的复合结构上.
主要成果:
- 预测巨大的反弹性热量效应与显著的热温度 (ΔT ≈ 23 K) 和同热 (ΔS ≈ 200 J kg−1 K−1) 在室温附近发生变化.
- 达到75MPa的适度压力应力,可实现大量的冷却.
- 在制冷效率 (ΔT/Δσ ≈ 500 K GPa−1) 和热导率 (κ ≈ 12 W m−1 K−1) 中表现出一级的改善.
- 在压力应变下观察到巨大的可逆弹性热量效应,具有最小的歇斯底里和没有机械疲劳.
结论:
- 复合烯和碳纳米管/石墨烯架构在固态制冷中表现出极好的弹性热量性能.
- 开发的材料提供了高效且持久的冷却解决方案.
- 为无形聚合物提供原子级理解和设计指南,并为室温应用提供eCE.
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