通过通过单晶到单晶的激烈转换,通过软离子金属有机框架选择性捕获金属阴离子
Jian Tian1, Laxmikant V Saraf, Birgit Schwenzer
1Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
Journal of the American Chemical Society
|May 29, 2012
概括
灵活的阳离子金属有机框架 (MOF) 通过阴离子插入转化为中性系统. 这一过程改变了框架的大小,并使过渡金属能够选择性地吸收性金属.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
背景情况:
- 阴离子金属有机框架 (MOF) 是具有调节性质的多功能材料.
- 从单晶到单晶的转换提供了受控的材料修饰.
研究的目的:
- 研究柔性阴离子MOF转化为中性异金属系统的过程.
- 探索这些转型过程中的结构变化和选择性.
主要方法:
- 单晶转化为单晶 (SC-SC) 通过阴离子插入.
- 描述MOF的结构和框架动态.
- 使用各种金属离子对阴离子吸收选择性的研究.
主要成果:
- 阳离子MOF成功转化为中性异金属系统.
- 由于合作债券的动态,框架显示出显著的体积变化 (高达33%).
- MOFs对二价过渡金属 (Co2+,Ni2+) 与金属 (Li+,Na+) 具有很高的选择性.
结论:
- 阴离子插入为受控的MOF转换提供了一条途径.
- 灵活的MOF可以经历实质性的结构变化,同时保持结晶性.
- 这些转变的MOF显示出选择性金属离子分离和捕获的前景.
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