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在低电场下产生巨大的电热效应

Xiaoshi Qian^1,2, Donglin Han³, Lirong Zheng⁴

¹Institute of Refrigeration and Cryogenics, Interdisciplinary Research Centre for Metamaterials and Intelligent Systems, State Key Laboratory of Mechanical System and Vibration, and MOE Key Laboratory for Power Machinery and Engineering, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China. xsqian@sjtu.edu.cn.

|December 23, 2021

概括

研究人员开发了一种用于高效冷却的新型电热聚合物. 这种新材料在中等电场下表现出显著的温度变化,性能优于现有的EC聚合物,为实用的热铺平了道路.

科学领域:

材料科学
热力学
聚合物化学

背景情况:

几十年来对电热效应 (EC) 材料和多层芯片的研究已经实现了热热的最小温度变化 (5K).
目前的EC材料需要高电场,导致降解和疲劳,限制实际应用.

研究的目的:

报告一种具有增强性能的新型EC聚合物.
研究导致EC性能改善的结构变化.
评估材料是否适用于实际的热应用.

主要方法:

通过将乙烯组转化为共价双键,合成了一种改性聚乙烯化物-三乙烯-乙烯聚合物.
在不同电场下描述了电热性质,包括和温度变化.
在100万个循环中评估材料性能和稳定性.

主要成果:

这种新型EC聚合物在50 MV m-1时显示EC变化为37.5 J kg-1 K-1和温度变化为7.5 K.
与同样的场强度下的最先进的EC聚合物相比,温度变化提高了275%.
结构修改增加了极点和极点-非极点接口区域,导致具有低切换能量障碍的高状态.

结论:

开发的EC聚合物在中等电场下表现出卓越的性能和稳定性.
结合共价双键的策略为设计先进的EC材料提供了一个有前途的途径.
由于其提高了效率和耐用性,该材料在实际热应用中具有显著的潜力.

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