基于过渡金属的磁性制冷剂用于室温应用
O Tegus1, E Brück, K H J Buschow
1Van der Waals-Zeeman Institut, Universiteit van Amsterdam, The Netherlands.
Nature
|January 24, 2002
概括
研究人员发现了一种新材料,MnFeP0.45As0.55,用于高效的室温磁性制冷. 这种材料具有很大的磁热效应 (MCE),为传统冷却方法提供了有希望的替代方案.
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.
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 磁性制冷利用磁热效应 (MCE) 作为传统蒸汽循环制冷的可持续替代方案.
- 在MCE中,磁场应用/移除后,磁性材料进行加热/冷却,从而实现热传递.
- 现有的MCE材料往往具有局限性,例如在室温以下运行.
研究的目的:
- 发现和描述一种在室温下呈现大MCE的新材料.
- 评估这种新材料在实际磁性制冷应用中的潜力.
- 了解对观察到的MCE负责的潜在物理机制.
主要方法:
- 合成和表征MnFeP0.45As0.55化合物. 这种化合物的合成和表征.
- 在变化的磁场 (2T和5T) 下测量磁变化.
- 确定材料的库里温度和制冷剂容量.
主要成果:
- 发现了MnFeP0.45As0.55,这是一个基里温度约为300K (室温) 的材料.
- 获得了14.5 J K-1 kg-1 (2 T) 和18 J K-1 kg-1 (5 T) 的大的磁变化.
- 与Gd相比,证明了较高的制冷剂容量和与Gd5Ge2Si2等巨型MCE材料相比的可比变化,但是在室温下.
结论:
- 由于MCE很大,MnFeP0.45As0.55是室温磁性制冷的一个有前途的材料.
- 观察到的大型MCE归因于现场诱导的第一阶段过渡.
- 这一发现提供了一种可行,高效和潜在的环保冷却技术.
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