一种有前途的低温磁性制冷剂
Qiaofei Xu1, Boliang Liu1, Mingyu Ye1
1Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
Journal of the American Chemical Society
|July 21, 2022
概括
研究人员开发了新的磁性制冷剂,用于无磁化制冷. 这些材料在低温下具有很大的磁热效应 (MCE),提高了冷却效率.
科学领域:
- 材料科学
- 凝聚物质物理学
- 热力学
背景情况:
- 无磁化制冷需要在广泛的温度范围内具有较大的磁热效应 (MCE) 的磁性制冷剂,并在亚凯尔文区域具有较低的磁性排序温度 (To).
- 由于需要低To,弱磁相互作用和高磁密度,开发这种材料具有挑战性.
研究的目的:
- 合成和描述基于Gd(OH) 3-xFx的新型磁性制冷剂.
- 研究离子加入对氧化物磁性和MCE的影响.
主要方法:
- 合成Gd(OH) 3-xFx化合物 (x = 1, ≈1.5, 2).
- 测量热容量和磁性.
- 在低凯尔文温度范围内分析磁热效应 (MCE).
主要成果:
- 引入离子到抗铁磁性Gd (OH) 3中有效调节了其磁性排序温度 (T).
- 化合物3 (Gd(OH) 1.5F2) 的To值为0.5K.
- 化合物3在0. 54K温度范围内显示出较大的MCE.
结论:
- Gd(OH) 3-xFx化合物代表了一个有前途的磁性制冷剂类别,用于基尔文以下的冷却应用.
- 根据MCE,化合物3被确定为迄今为止在0.54K范围内报告的最佳磁性制冷剂.
- 在磁性制冷剂中加入是一种可行的调整To和增强MCE的策略.
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