在金属有机框架中调节热膨胀,使用混合链接固体溶液方法
Samuel J Baxter1, Andreas Schneemann1, Austin D Ready1
1Sandia National Laboratory , Livermore , California 94550 , United States.
Journal of the American Chemical Society
|July 20, 2019
概括
研究人员通过创建固体解决方案,在金属有机框架 (MOF) 中连续调整负向正热膨胀. 这一突破为MOF的热性能提供了新的控制.
科学领域:
- 材料科学
- 化学学
- 固态物理
背景情况:
- 已知金属有机框架 (MOF) 具有负热膨胀 (NTE).
- 在单个MOF阶段内,热膨胀的持续调整从负到正没有以前报告过.
- 传统的NTE材料缺乏这种可调性特性.
研究的目的:
- 在MOF系统中研究热膨胀的连续调整.
- 探索单相固体溶液的形成以控制热膨胀.
- 建立一个适合MOF的热膨胀的总体策略.
主要方法:
- 在Zn-DMOF-TM系统中合成一系列混合链接固体溶液.
- 合成的MOF的热膨胀特性.
- 对影响热膨胀行为的结构变化的分析.
主要成果:
- 在四边形材料的a-b平面中观察到从负向正热膨胀的平滑过渡.
- 零热膨胀的温度从~186K转移到~325K随着TM-bdc含量的增加.
- 单相固体溶液的成功形成使得持续的热膨胀调整成为可能.
结论:
- 混合链接固体溶液是控制MOF热膨胀的可行和一般策略.
- 这项工作证明了单个MOF系统中热膨胀的前所未有的可调性.
- 这些发现为设计具有特定热膨胀特性的MOF铺平了道路.
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