在二维共价有机框架中进行层间转移
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
概括
溶解导致二维共价有机框架 (2D COF) 从AA堆叠到准AB结构. 这种溶剂诱导的重新排列在二维COF中很常见,并影响其特性.
科学领域:
- 材料科学
- 化学学
- 晶体学
背景情况:
- 层叠结构在二维共价有机框架 (2D COF) 中普遍存在.
- 与没有溶剂的对应物相比,二维COF的结构行为在很大程度上仍未被探索.
研究的目的:
- 调查和确定2DCOF的现场结构.
- 了解化和干燥的二维COF之间的结构差异.
- 探索二维COF中溶剂诱导的结构变化的普遍性.
主要方法:
- 在现场测定二维COF结构.
- 粉末X射线衍射 (PXRD) 数据分析.
- 计算模型包括密度函数理论 (DFT) 和Pawley精细化.
主要成果:
- 溶解的2DCOF表现出显著的层间移动,形成准AB堆叠结构,与干燥状态的AA堆叠不同.
- 溶剂的相互作用削弱了层间的吸引力,促进了这种结构的重新排列.
- DFT的计算证实了近似AB堆叠在化COF中的能量偏好.
- 这种现象在四个不同的晶体二维COF中观察到,表明普遍性.
结论:
- 在二维COF中,solvation诱导了从AA到准AB的通用层间堆叠重排.
- 这些发现需要重新评估二维COF结构.
- 溶剂引起的结构变化为COF在潮湿条件下的应用开辟了新的途径.
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