在金属有机框架中的相关缺陷纳米域的直接成像
Duncan N Johnstone1, Francesca C N Firth2, Clare P Grey2
1Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, U.K.
Journal of the American Chemical Society
|July 7, 2020
概括
扫描电子衍射 (SED) 弥合了金属有机框架 (MOF) 的纳米尺度表征差距. 这种技术可以对缺陷的纳米领域进行图像化,从而能够更好地控制MOF的微观结构,从而提高性能.
科学领域:
- 材料科学
- 晶体学
- 纳米技术
背景情况:
- 缺陷工程对于提高金属有机框架 (MOF) 性能至关重要.
- 在多个长度尺度上描述缺陷分布对于MOF设计至关重要.
- 在MOF缺陷分析中,大量和亚纳米技术之间存在差距.
研究的目的:
- 弥补MOF中纳米尺度表征的差距.
- 展示扫描电子衍射 (SED) 作为成像缺陷纳米领域的工具.
- 为了更好地控制MOF的微观结构.
主要方法:
- 使用扫描电子衍射 (SED) 进行纳米级晶体分析.
- 使用低剂量成像来形成衍射对比图像.
- 在UiO-66 ((Hf) MOF中分析缺陷的纳米域,用于高分辨率的大面积.
主要成果:
- 在UiO-66 ((Hf) MOF中,SED成功成像了缺陷的纳米域. 1000 nm区域,大约 5纳米的分辨率).
- 揭示了域形态和分布,表明了晶体生长过程.
- 在MOF结构中确定了位移和小角粒边界.
结论:
- SED 弥合了 MOF 的纳米表征差距.
- SED有助于对MOF微结构的理解和设计.
- SED是通过缺陷控制推进功能MOF设计的关键技术.
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