Tc = 26から80Kまでの溶媒誘導の2Dセミキノンラジカルを含む微孔磁石
Ie-Rang Jeon1, Bogdan Negru1, Richard P Van Duyne1
1Department of Chemistry, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.
Journal of the American Chemical Society
|November 18, 2015
まとめ
研究者らはテトラオクソレンのラジカルリガンドを使って 新しい微孔磁石を作りました この新しい材料は自発的な磁気化と高い表面積を示し,高度な磁気アプリケーションの道を開きます.
科学分野:
- 材料科学
- 無機化学
- マグネティズム
背景:
- テトラオクソレンリガンドは,機能的な材料を構築する可能性を秘めた酸化還元活性分子である.
- 毛細な磁気固体の開発は,触媒,ガス貯蔵,およびセンシングのアプリケーションに不可欠です.
研究 の 目的:
- テトラオクソレン・ラジカル・ブリッジリング・リガンドを 微孔質の磁気固体に組み込む
- 材料の構造,電子特性,磁気的振る舞いを特徴づけること.
主な方法:
- 2,5-ジクロル-3,6-ジヒドロキシ-1,4-ベンゾキノン (LH2) と Fe ((II) の金属化.
- 構造と電子分析のためのX線微分法,ラーマン光譜法,モースバウアー光譜法.
- 表面積の測定のためのN2吸収と磁気特性のDC磁気感受性の測定.
主要な成果:
- 固体の形成は,自発的な電子移転により,Fe (III) センターと混合バレンスのリガンドが形成される.
- BET表面積が885 m2/gの解溶相が得られた.
- 80 K (溶解) と26 K (活性化) 以下の自発磁化が観察され,磁気ヒステリシスはそれぞれ60 Kと20 Kまでであった.
結論:
- レドックス活性テトラオクソレンリガンドは,微孔磁石の形成をサポートすることができます.
- この研究は,構造的に特徴づけられた最初のテトラオクソレン基結合体を含む拡張固体を提示する.
- 開発された材料は,多孔性の磁気固体を必要とするアプリケーションに希望を示しています.
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