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在共价有机框架中的正方形网的纠

Fangying Jin1, Ha L Nguyen1,2, Zhiye Zhong3

  • 1Department of Chemistry, University of California-Berkeley, Kavli Energy Nanoscience Institute at UC Berkeley, and Berkeley Global Science Institute, Berkeley, California 94720, United States.

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概括

研究人员合成了第一个纠的二维方形共价有机框架 (COF). 这一突破利用了一种新的SFTB建筑单元,防止π-π堆叠,并为先进的材料设计提供纠.

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科学领域:

  • 材料科学
  • 超分子化学
  • 有机化学

背景情况:

  • 共价有机框架 (COF) 是具有可调节性质的晶体多孔聚合物.
  • 2D COF通常表现出强大的π-π堆叠,阻碍复杂架构的形成.
  • 开发控制COF拓和防止聚合的策略对于高级应用至关重要.

研究的目的:

  • 合成新的纠的二维方形COF结构.
  • 调查 SFTB 建筑单元在防止 π-π 堆叠和使纠的作用.
  • 为创建复杂的COF架构建立新的设计原则.

主要方法:

  • 两种新的二维COF,COF-38和COF-39的合成,使用4,4',4′′′-9,9'-spirobi[fluorene]-2,2',7,7'-tetrayl) -tetrabenzaldehyd (SFTB) 和p-phenylenediamine (PPA) 或benzidine (BZD).
  • 单晶电子衍射分析以确定COF-39的结构.
  • 使用扭曲的四面体SFTB构建块来控制框架组装.

主要成果:

  • 成功合成了COF-38和COF-39,这是第一个纠的二维方形COF结构的例子.
  • 对COF-39的结构阐明,揭示相互纠的2D方形网 (sql拓).
  • 证明 SFTB 建筑单元有效地防止 π-π 堆叠,促进纠网络的形成.

结论:

  • SFTB 建筑单元是克服二维 COF 的 π-π 叠加的关键,使得纠结构的形成成为可能.
  • 这项工作引入了设计复杂和相互关联的COF架构的新策略.
  • 这些发现大大提高了对共价有机框架的理解和设计原则.