溶媒と圧力の誘発による2つの3D銅グルタレートベースの金属有機フレームワークの相変化,グルタレート (+gauche -gauche) による適合性同位体
Charl X Bezuidenhout1, Vincent J Smith1, Catharine Esterhuysen1
1Department of Chemistry and Polymer Science, University of Stellenbosch , Matieland 7602, South Africa.
Journal of the American Chemical Society
|April 1, 2017
まとめ
2つの柔軟な金属有機フレームワーク (MOF) は,銅 (II) グルータレート柱で溶媒の損失時に自発的に相変化し,狭いチャネルを作成します. 一つのMOFは選択的にCO2を吸収し,より広いチャネル形式に戻します.
科学分野:
- 材料科学
- クリスタルグラフィー
- 化学工学
背景:
- メタル・オーガニック・フレームワーク (MOF) は,調整可能な構造を持つ高度な多孔性材料です.
- 柔軟なMOFは,外部の刺激に反応して構造的変化を示すことができます.
- フレームワークのダイナミクスを理解することは,特定のアプリケーションのためのMOFの設計に不可欠です.
研究 の 目的:
- 柔軟な柱を持つ2つのイソレテキュラー銅 (II) 基MOFの相行動を調べる.
- 構造的変化とその多孔性への影響を特徴づける.
- 柔軟なMOFのCO2吸収特性とメカニズムを探求する.
主な方法:
- 構造分析のための単結晶X線微分法 (SCXRD).
- ガス吸収研究のための吸収同熱測定
- ガスを含む構造物を隔離するための超臨界CO2.
- 解明のための分子モデリングシミュレーション.
主要な成果:
- 2つのMOF, [Cu2 ((glu) 2 ((bpa)) ]と [Cu2 ((glu) 2 ((bpp)) は,溶媒の損失で自発的な相変化を狭いチャネル形式にします.
- 狭いチャネル形式は,溶媒でアクセス可能な量が大幅に減少しています.
- [Cu2 ((glu) 2 ((bpa)) ]は,二酸化炭素圧力の下での広チャンネル形への可逆変換を示す,段階的な二酸化炭素吸収同熱体を示しています.
- SCXRDはフレームワークチャネル内のCO2分子の位置を決定した.
- 分子モデリングにより,相変化メカニズムと関連するエネルギーが解明されました.
結論:
- 柔軟な柱状層のMOFは,溶媒の除去時に重要な構造変化を示すことができます.
- [Cu2 ((glu) 2 ((bpa)) ]の可逆相変化により,選択的なCO2吸収が可能である.
- これらのダイナミックな構造的変化を理解することは,ガス分離および貯蔵アプリケーションのためのMOFの設計の鍵です.
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