NaCl型FePt-MnOバイナリナノ結晶超網状の熱安定性と磁気特性が向上しました
Angang Dong1, Jun Chen, Xingchen Ye
1The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States. adong@lbl.gov
Journal of the American Chemical Society
|August 2, 2011
まとめ
私たちは,鉄・プラチナ・マンガン酸化物ナノ結晶を用いて,バイナリナノ結晶のスーパーラットスを製造しました. この方法は,相変換中に鉄・プラチナ・ナノ粒子の焼却を防止し,データ保存のためのオーダーされた鉄磁性配列を可能にします.
科学分野:
- マテリアルサイエンス 材料科学
- ナノテクノロジー ナノテクノロジー
- マグネチズム (磁気) とは
背景:
- 鉄・プラチナ (FePt) ナノ粒子は,硬磁性特性により,高密度データストレージに有望である.
- FePtナノ粒子をL1(0) 段階に変換すると,しばしばシンタリングが起こり,その秩序化された構造が劣化します.
- 段階変換中にナノ粒子の秩序を維持する方法を開発することは,アプリケーションにとって極めて重要です.
研究 の 目的:
- オーダーされたFePtベースのナノクリスタルスーパーラティスを製造する方法を開発する.
- FePt相変換に対する他のナノ結晶との共同組み立ての効果を調査する.
- 安定した,オーダーされたフェロ磁性ナノクリスタル配列をデータストレージのために作成することを可能にします.
主な方法:
- 鉄・プラチナ (FePt) とオキシド・マンガン (MnO) のナノ結晶を液体-空気界面で一緒に組み合わさって,バイナリ・スーパー・ラティス膜を形成する.
- バイナリスーパーラットスの熱熱解熱は650°CでFePtをL1(0) 段階に変換する.
- FePtのみの超網と無秩序な混合物との冷却されたバイナリ超網の比較分析.
主要な成果:
- NaCl型バイナリナノ結晶のスーパーラットスを成功裏に育てました.
- バイナリ超格子内のFePt NCsのL1(0) 段階への変換は,長距離順序を劣化させることなく達成された.
- FePtのみのスーパーラットと,同一のアニリング条件下での無秩序な混合物において,有意なFePtシンター化が観察されました.
- コアセンブリは,L1 (((0) 段階変換中にFePtのシンタリングを防ぐことが実証されました.
結論:
- FePt NCをバイナリ・スーパーグリットに組み込むことは,硬磁性L1(0) 段階への変換中にシントリングを効果的に防止します.
- このアプローチは,オーダーされたフェロ磁性ナノクリスタル配列を製造するための新しい経路を提供します.
- 開発された方法は,高密度データストレージアプリケーションにおいて有望である.
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