室温 ブロックされた磁性ナノ粒子は,3段階の熱分解プロセスによって促進されたフェライトに基づいています
Kevin Sartori1,2, Fadi Choueikani2, Alexandre Gloter3
1Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 , F-67000 Strasbourg , France.
Journal of the American Chemical Society
|June 1, 2019
まとめ
オニオン型の構造を持つ稀土の磁性ナノ粒子は,磁性アニソトロピーが強化されています. これらの16nmの鉄酸化物ベースのナノ粒子は 室温でブロックされていて 永久磁石の応用が期待されています
科学分野:
- 材料科学
- ナノテクノロジー
- マグネティズム
背景:
- 硬質と軟質の磁気相を組み合わせた交換結合ナノ粒子は,磁気アニソトロピーを強化します.
- 稀土のない磁性ナノ粒子の室温阻害を20nm以下で達成することは,シンプルなコアシェル構造では依然として課題です.
研究 の 目的:
- 強化された磁気特性を有する新しい磁気ナノ粒子を開発する.
- 室温阻害の可能性を調査する 希土のないナノ粒子
主な方法:
- 熱分解に基づいた3段階の種子媒介成長アプローチを使用した.
- 製造されたコア・シェル・シェルナノ粒子は,酸化鉄のコア,コバルトドーピングされたフェライト中間殻,および外部の酸化鉄の殻を持つ.
主要な成果:
- 16nmの磁性ナノ粒子を 合成しました
- core@shellとshell@shellのインターフェイスでダブル交換カップリングにより,磁性アニソトロピーエネルギーが著しく増加したことが実証されました.
- 鉄酸化物を基にしたナノ粒子で 室温を遮断します
結論:
- オニオン型の磁性ナノ粒子の構造は,磁性アニソトロピーを効果的に強化し,室温ブロックを可能にします.
- これらの発見は,先進的な希土のない永久磁石の開発に非常に有望です.
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