金属有机框架中的可逆结晶性维护相位过渡:发现,机械研究和潜在的应用
Dahuan Liu1, Tian-Fu Liu, Ying-Pin Chen
1‡State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China.
Journal of the American Chemical Society
|May 27, 2015
概括
一个新的金属有机框架 (MOF),PCN-526,表现出可逆的单晶到单晶 (SC-SC) 阶段过渡,由火引发. 这种转变为设计响应的发光MOF材料提供了一个新的平台.
科学领域:
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
- 化学 化学 化学
背景情况:
- 在金属有机框架 (MOF) 中,单晶到单晶 (SC-SC) 阶段过渡是常见的.
- 之前的研究经常描述结构变化,但缺乏对这些转变的机制理解.
- 金属有机框架为先进的材料应用提供可调节的特性.
研究的目的:
- 在MOF PCN-526.6中发现和描述一个火触发的可逆SC-SC相位过渡.
- 调查观察到的相位过渡背后的机制.
- 探索PCN-526作为响应性发光材料的平台的潜力.
主要方法:
- 金属有机框架PCN-526.6的合成和表征.
- 在现场监测使用X射线衍射的相变.
- 修改外框架金属离子以探测过渡机制.
- 对发光客分子进行封装,以研究光发光调制.
主要成果:
- 在PCN-526火后观察到可逆的SC-SC相过渡,道扭曲从方形到矩形,同时保持单晶性.
- 改变外框架金属离子的占用或物种被发现可以抑制相位过渡,提供机械洞察力.
- 在客分子封装后,PCN-526显示了可调节的光发光特性.
- 检测到与SC-SC转换相关的响应性发光.
结论:
- 在PCN-526中发现火触发的SC-SC相转换为MOF转换提供了一个新的机制.
- 了解外框架金属离子的作用对于控制MOF相位过渡至关重要.
- PCN-526 作为一种多功能平台,用于开发具有刺激反应性质的新型发光MOF材料.
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