2次元の共性有機フレームワークにおける層間シフト
Chengjun Kang1, Zhaoqiang Zhang1, Vanessa Wee1
1Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117585, Singapore.
Journal of the American Chemical Society
|July 8, 2020
まとめ
溶解により二次元共性有機フレームワーク (2D COF) の層の積み重ねがAAから準AB構造に変化する. この溶媒による再配置は2DCOFで一般的であり,その性質に影響します.
科学分野:
- 材料科学
- 化学について
- クリスタルグラフィー
背景:
- 層の積み重ね構造は二次元共性有機フレームワーク (2D COF) で一般的です.
- 溶媒のないCOFと比較して,2DCOFの構造的行動はほとんど未研究のままである.
研究 の 目的:
- 溶解された2D COFの in situ 構造を調査し,決定する.
- ソルバットと乾燥した2DCOFの構造的な違いを理解する.
- 2D COFにおける溶媒による構造変化の普遍性を探求する.
主な方法:
- 溶解された2D COF構造の現地測定
- 粉末X線微分 (PXRD) データ分析
- 密度関数理論 (DFT) とパウリー精錬を含む計算モデリング.
主要な成果:
- ソルバットされた2DCOFは,乾燥状態のAAスタッキングとは異なる準ABスタッキング構造を形成する,重要な層間シフトを示す.
- 溶媒の相互作用は層間の引き寄せを弱め,この構造的再配置を容易にする.
- DFTの計算は,ソルバットされたCOFで準ABの積み重ねをエネルギー的に好むことを確認しています.
- この現象は4つの異なる結晶2DCOFで観察され,普遍性を示した.
結論:
- 溶解は2D COFのAAから準ABへの普遍的な層間堆積の再配置を誘導する.
- これらの発見は,ソルバット状態の2DCOF構造の再評価を必要とします.
- 溶媒によって引き起こされる構造の変化は,COFの湿った環境での応用に新しい道を開く.
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