通过现场可变温度液体细胞传输电子显微镜和现场X射线衍射直接监测金属-有机框架中的相位过渡
Jiafei Lyu1,2,3, Xinyi Gong3, Seung-Joon Lee3
1Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China.
Journal of the American Chemical Society
|February 19, 2020
概括
研究人员发现了基于Zr6的金属有机框架 (MOF) 的相位过渡. 在scu-NU-906到csq-NU-1008中观察到的这种微孔变异是通过溶解和沉发生的.
科学领域:
- 材料科学
- 化学学
- 纳米技术
背景情况:
- 基于Zr6的金属有机框架 (MOF) 具有四级链接器,可提供结构调整性.
- 多态性是常见的,但这些MOF中的相位过渡很少被报告.
- 了解多态转换对于开发纯相材料至关重要.
研究的目的:
- 发现和描述基于Zr6的MOF中的相位过渡.
- 研究微孔转化为半孔的机制.
- 了解合理材料设计的多态转换.
主要方法:
- 在现场可变温度液体细胞传导电子显微镜 (VT-LCTEM).
- 高分辨率传输电子显微镜 (HRTEM).
- 在现场可变温度粉末X射线衍射 (VT-PXRD).
主要成果:
- 观察到从微孔的scu-NU-906到中孔的csq-NU-1008的相变.
- 使用先进的现场显微镜和衍射技术监测了这种变化.
- 在酸中通过溶解-沉机制进行微孔转化.
结论:
- 基于Zr6的MOF中的相过渡可以使用现场技术进行研究.
- 溶解-沉是scu-NU-906转化为csq-NU-1008的机制.
- 这一发现有助于合理设计纯相MOF材料.
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