在强大的金属有机框架中进行合成后的配体和离子交换
Min Kim1, John F Cahill, Honghan Fei
1Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA.
Journal of the American Chemical Society
|October 9, 2012
概括
联体和金属离子的合成后交换 (PSE) 在强大的金属有机框架 (MOF) 中很常见. 这一过程使得创建新型MOF材料成为可能,这是通过传统合成无法实现的.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 纳米技术纳米技术
背景情况:
- 金属有机框架 (MOF) 是先进的多孔材料,具有多样化的应用.
- 一些MOF的惰性限制了它们在合成后的修饰.
- 了解交换过程对于MOF材料设计至关重要.
研究的目的:
- 调查强的MOF中的联体和金属离子的合成后交换 (PSE).
- 为了证明PSE在创建新型MOF结构方面的合成实用性.
- 为了区分PSE与其他潜在的反应机制.
主要方法:
- 在各种MOF中研究了联体和金属离子交换,包括ZIF,MIL-53,MIL-68,MIL-101和UIO-66.
- 采用气溶飞行时间质谱法进行单颗粒子分析.
- 进行了控制实验,以排除溶解/再结晶和聚合机制.
主要成果:
- 在温和条件下,在MIL-53 ((Al) 和MIL-68 ((In) 中轻易观察到联体PSE.
- 观察到的金属离子PSE在MIL-53 ((Al) 和MIL-53 ((Fe)) 之间.
- 通过PSE成功合成了UiO-66的第一个Ti(IV) 模拟物.
- 证实PSE是占主导地位的机制,即使在像UiO-66 ((Zr)) 这样的动力惰性框架中也是如此.
结论:
- 合成后交换 (PSE) 是强大的MOF中的通用和常见过程.
- PSE为新型MOF材料提供了一条强大的合成路线.
- 这种方法扩大了MOF功能化和应用的可能性.
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