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Gd(OH) F2: 有望な冷凍磁気冷媒
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
まとめ
研究者はアディアバティック解磁冷却のための新しい磁気冷媒を開発しました. これらの材料は低温で大きな磁熱効果 (MCE) を発揮し,冷却効率を改善します.
科学分野:
- 材料科学
- 凝縮物質物理学
- 熱力学
背景:
- アディアバティック脱磁冷却には,広範囲の温度範囲で大きな磁熱効果 (MCE) を有する磁気冷媒と,サブケルビン領域で低い磁気配列温度 (To) が必要です.
- このような材料の開発は,低いTo,弱い磁気相互作用,および高い磁気密度の必要性のために困難です.
研究 の 目的:
- Gd(OH) 3-xFxを基にした新しい磁気冷媒を合成し,特徴づけること.
- ガドリニウム水酸化物の磁性およびMCEに対するフッ素アニオンの組み込みの影響を調査する.
主な方法:
- Gd(OH) 3-xFx化合物の合成 (x = 1, ≈1.5, 2)
- 熱容量と磁気特性の測定
- ケルビン以下温度範囲における磁熱効果 (MCE) の分析.
主要な成果:
- フッ化物アニオンの導入により,反鉄磁性Gd (OH) 3は磁性秩序温度 (To) を効果的に調節した.
- 化合物3 (Gd(OH) 1.5F2) はTo 0.5Kを示した.
- 化合物3は0. 5~4Kの温度範囲で大きなMCEを示した.
結論:
- Gd(OH) 3-xFx化合物は,ケルビン未満の冷却アプリケーションのための有望な磁気冷媒のクラスを表しています.
- 化合物3は,MCEに基づいて0. 5〜4Kの範囲で,これまでに報告された最高の磁気冷媒として特定されています.
- フッ素の組み込みは,磁気冷媒におけるToとMCEの強化のための実行可能な戦略を提供します.
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