多変性金属有機フレームワークにおける金属の配列化
Zhe Ji1,2,3,4, Tong Li5, Omar M Yaghi6,2,3,4,7
1Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|August 9, 2020
まとめ
研究者は金属・有機構造の 74個の結晶に金属の配列をマッピングした. 異なる合成条件により,様々な金属イオン配列が生み出され,MOFが示された.
科学分野:
- 材料科学
- 化学について
- ナノテクノロジー
背景:
- メタル・オーガニック・フレームワーク (MOF) は,調節性特性を有する多用性のある多孔性材料です.
- 複数の金属イオンを含む多変量MOFは,機能が強化されています.
- MOFの金属イオン分布を理解することは,高度な材料の設計に不可欠です.
研究 の 目的:
- 多変性金属有機構造-74 (MOF-74) の結晶内の異なる金属イオンの空間的配置を調査する.
- 合成条件 (温度,金属タイプ) と観測された金属配列パターンを相関させる.
- 混合金属MOF-74における金属配列の異質性を特徴付ける.
主な方法:
- コバルト (Co),カドミウム (Cd),鉛 (Pb),マンガン (Mn) の組み合わせによる多変量MOF-74結晶の合成
- 原子探査トモグラフィー (APT) を使用して,MOF結晶内の金属イオンの分布を空間的にマッピングしました.
- 異なる合成温度と金属組成に基づいた金属配列の分析
主要な成果:
- ランダム (Co,Cd,120°C),短重複 (Co,Cd,85°C),長重複 (Co,Pb,85°C),挿入 (Co,Mn,85°C) という4種類の金属配列が特定されました.
- コバルトのモラー分数は,配列のタイプを変えることなく,サンプル全体で0. 4から0. 9に変化しました.
- MOF-74は,異なるサイズの金属イオンに高い耐性を示し,多様な配列形成を可能にしました.
結論:
- 合成条件は多変量MOF-74における金属イオンの空間的配置に大きな影響を与える.
- 原子探査トモグラフィーは,MOF構造内の複雑な金属イオン順序を解明するのに有効です.
- MOF-74の構造的柔軟性により,様々な異質な金属の配列が形成され,特別の材料の設計の道が開きます.
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