4.7nmの孔を持つ2Dの共性有機フレームワークと,その層間堆積の洞察
Eric L Spitler1, Brian T Koo, Jennifer L Novotney
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
Journal of the American Chemical Society
|October 22, 2011
まとめ
研究者は,効率的な電荷輸送のための記録的な大きな孔を持つ新しい2D共性有機フレームワーク (COF) を合成しました. 先進的な計算により,典型的な覆われた構造と異なるユニークな層間堆積が明らかになった.
科学分野:
- 材料科学 材料科学とは
- ナノテクノロジー ナノテクノロジー
- 有機化学 オーガニック・ケミストリー
背景:
- 二次元の層状コヴァレンント有機フレームワーク (2D COF) は,エクシトンと電荷輸送に有益な秩序付けられたπ電子システムを提供します.
- 永続的な多孔性により,多用途な機能化が可能である.
- 強化された構造特性を持つCOFの開発は,高度なアプリケーションにとって不可欠です.
研究 の 目的:
- これまでに報告された最大の孔を持つ2D COFを合成する.
- COFをマイクロ結晶粉と垂直方向の薄膜形式の両方で準備するために.
- 合成されたCOFの層間距離と堆積を調査する.
主な方法:
- 2,3,6,7,10,11-ヘキサヒドロキシトリフェニレン (HHTP) と4,4'-ディフェニルブタディネビス (ボロン酸) (DPB) の間の凝縮反応.
- グラフェン/融解シリカ基板の上にマイクロクリスタリン粉末および薄膜を調製する.
- 分子ダイナミクスと密度関数理論 (DFT) の計算.
主要な成果:
- 前例のないほど大きな毛穴を持つ2D COFの合成が成功しました.
- COFの特徴は,高表面積の粉末と垂直方向の薄膜の両方である.
- 計算分析により,隣接する層間の水平偏差は1.7-1.8 Åであり,遮られたAAスタッキングからの偏差を示した.
結論:
- 合成された2DCOFは,例外的に大きな毛穴を有し,COFの設計を進めている.
- グラフェン上に薄膜の形で材料を準備することで,デバイスの統合の道が開きます.
- 発見された層間のオフセットは,COFの構造的多形性とパッキングに関する新しい洞察を提供します.
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