单个金属有机框架微晶的压缩诱导变形
Zhi Su1, Yu-Run Miao, Shi-Min Mao
1Department of Chemistry and ‡Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|January 31, 2015
概括
焦化物-伊米达酸框架 (ZIF-8) 微晶在压力下经历显著的体积减小和无形化. 溶酸盐极大地改变了ZIF-8的机械性能,使其变形不易,易碎.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 化学工程是化学工程的重要组成部分.
背景情况:
- 焦化物-胺酸框架 (ZIFs) 是一类金属有机框架,以其可调节的结构和应用而闻名.
- 了解微尺度ZIF的机械性能对于它们在各种工程应用中的使用至关重要.
- 这一类的杰出成员ZIF-8具有独特的结构和化学特征.
研究的目的:
- 在压缩下研究单个地质石-意达酸框架 (ZIF-8) 微和亚微晶体的变形和机械行为.
- 为了确定Young的模量和体积变化作为单个ZIF-8晶体施加压力的函数.
- 探索酸盐,尺寸和方向对ZIF-8晶体机械性能的影响.
主要方法:
- 在单个ZIF-8微和亚微晶体上进行压缩实验.
- 在变压下测量扬模和体积变化.
- 研究晶体的行为 (变形,无形化,恢复) 到4 GPa.
- 对溶剂,尺寸和方向对机械反应的影响的分析.
主要成果:
- 个别的ZIF-8微晶体在压缩 (0-4 GPa) 时表现出显著的体积减少和无形化.
- 变形的ZIF-8微晶体在释放压力后显示部分体积恢复.
- 与溶解晶体相比,甲醇溶解的ZIF-8微晶体明显不那么容易变形和破碎.
- 导向和尺寸影响了ZIF-8纳米和微晶体的机械行为.
结论:
- ZIF-8晶体的机械行为强烈依赖于它们的形态学,大小和酸盐的存在.
- 压缩导致ZIF-8微晶体的显著结构变化,包括无形化.
- 溶解状态在决定ZIF-8单晶的机械完整性和可变性方面起着至关重要的作用.
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