AlFe2B2におけるマグネトカロリック効果:地球に豊富に存在する元素からの磁気冷媒へ
Xiaoyan Tan1, Ping Chai, Corey M Thompson
1Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, Florida 32306, United States.
Journal of the American Chemical Society
|June 5, 2013
まとめ
研究者らは,軽量の磁気材料であるAlFe2B2を開発した. 室温近くで有意な磁熱効果 (MCE) を示し,稀土元素の有望な代替品となっています.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- 固体化学 固体化学
背景:
- 効率的なマグネトカロリー材料の探求は,先進的な冷却技術の開発に不可欠です.
- 層状金属ボリドは,新しい磁気特性とアプリケーションの可能性を秘めています.
- マグネトカロリー材料にしばしば使用される希土元素は,供給とコストの課題に直面しています.
研究 の 目的:
- AlFe2B2化合物を合成し,特徴づけること.
- AlFe2B2.2.の磁性および磁熱性特性を調査する.
- AlFe2B2の希土のないマグネトカロリック材料としての可能性を評価する.
主な方法:
- アークメルトリングとGaフクロックスによる合成方法.
- 層状結晶構造の構造分析. 層状結晶構造の構造分析.
- フェロマグネティズムとオーダー温度を決定するための磁気測定.
- マグネトカロリック効果 (MCE) の測定は,磁場の関数として行われます.
主要な成果:
- AlFe2B2が成功して合成され,Alと[Fe2B2]の層を交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互を交互に交互に交互に交互を交互に交互に交互に交互を交互に交互を交互に交互に交互を交互に交互に交互を交互に交互に交互に交互を交互に交互に交互を交わした.
- この化合物は,キュリー温度307Kの移動性鉄磁気性を示しています.
- 重要なマグネトカロリー効果が観察された: 2 T で 4.1 J kg (−1) K (−1)) と 5 T で 7.7 J kg (−1) K (−1) です.
- これらのMCE値は,金属ボリドおよび室温に近い122ファミリー材料で報告された最高値です.
結論:
- AlFe2B2は,希土のない有望なマグネトカロリック材料です.
- その軽量な性質と,地球に豊富に存在する元素の使用は,環境に優しい,費用対効果の高いものとなっています.
- 室温に近いMCEは,磁気冷却アプリケーションの潜在力を強調しています.
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