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Updated: Aug 23, 2025

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Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
Published on: May 29, 2018
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エントロピー工学とスピネル高エントロピー酸化物の調整可能な磁気順序
Graham H J Johnstone1,2, Mario U González-Rivas1,2, Keith M Taddei3
1Department of Physics & Astronomy, University of British Columbia, VancouverBC V6T 1Z1, Canada.
Journal of the American Chemical Society
|November 2, 2022
まとめ
スピネル構造を持つ高エントロピー酸化物は,ガリウム置換の影響で調節可能なフェリマグネティック・オーダーを示す. この置換はカチオン分布とエントロピーに影響を与え,先進的な材料設計のプラットフォームを提供します.
科学分野:
- 材料科学
- 固体化学
- マグネティズム
背景:
- スピネル酸化物は,高エントロピー酸化物 (HEO) の理解に不可欠である.
- HEOにおける構成エントロピー,場所の選択性,磁気性の相互作用.
- 複雑な酸化物系における磁気特性の研究は不可欠である.
研究 の 目的:
- スピネル (Cr, Mn, Fe, Co, Ni) 3O4の磁性特性を特徴付けるために.
- 非磁性ガリウム置換が磁性に与える影響を研究する.
- マグネティック・チューナビリティとカチオン・サイト・セレクティビティとエントロピーを相関させる.
主な方法:
- 磁気感受性の測定
- パウダーニュートロン反射
- X線吸収と磁気円形二重化スペクトロスコーピー
主要な成果:
- スピネルHEOのフェリ磁気順序は,40%のGa置換まで強固である.
- ガリウム置換は 温度,モメント,磁気硬さを 大きく調整します
- Mn,Co,Feの占有量が再分配され,強力な場所選択性が観察されました. Mnはバレンスの減少に対応します.
結論:
- ガリウム置換は,スピネルHEOの磁気特性を正確に制御します.
- 場所の選択性は構成エントロピーを影響し,安定性を高める可能性があります.
- スピネル酸化物は,低エントロピーから高エントロピーへのエントロピー工学のための調整可能なプラットフォームを提供します.
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