一个非常稳定的金属-有机框架,由酸基金属-有机多面体构成
Jerika A Chiong1, Jie Zhu1, Jake B Bailey1
1Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States.
Journal of the American Chemical Society
|April 1, 2020
概括
研究人员使用酸盐配体开发了一种稳定的金属有机框架 (MOF),Fe-HAF-1. 这种材料具有显著的化学稳定性,可以选择性地吸附带电物种,从而有效地分离着染料和其他分子.
科学领域:
- 材料科学
- 超分子化学
- 协调化学
背景情况:
- 金属有机框架 (MOF) 为各种应用提供可调节的特性.
- 开发具有特殊化学和水稳定的MOF仍然是一个重大挑战.
- 基于酸盐的协调化学提供了强大的框架材料的途径.
研究的目的:
- 合理设计和合成一个水稳定的金属有机框架 (MOF),使用基于酸盐的多面体.
- 研究新型Fe-HAF-1 MOF的稳定性和特性.
- 探索Fe-HAF-1在选择性离子吸附和分离方面的潜力.
主要方法:
- 合理设计和合成Fe-HAF-1 MOF.
- Fe-HAF-1 的结构和特性.
- 在广泛的pH范围 (1-14) 和强中评估化学稳定性.
- 对充电物种和有机染料的离子吸附和分离能力的研究.
主要成果:
- 成功合成了具有单核Fe3+节点和酸配体的水稳定MOF,Fe-HAF-1.
- Fe-HAF-1 在各种有机和水性溶剂,包括5M NaOH中表现出极好的稳定性.
- 在pH 4以上的Fe-HAF-1晶体上出现意想不到的负电荷,这归因于结晶缺陷.
- 已证明正电离子的选择性吸附和有机染料的尺寸选择性分离.
结论:
- Fe-HAF-1是一种基于酸盐的新型MOF,具有显著的稳定性和独特的离子特性.
- 该框架的缺陷导致的负荷使得负荷物种能够有效地分离.
- Fe-HAF-1扩展了基于酸盐的MOF库,并为分离技术提供了一个有前途的平台.
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