通过改装调整金属有机框架Cu3BTC2的负热膨胀行为
Christian Schneider1, David Bodesheim1, Michael G Ehrenreich1
1Department of Chemistry , Technical University of Munich , Lichtenbergstrasse 4 , Garching D-85748 , Germany.
Journal of the American Chemical Society
|June 12, 2019
概括
研究人员使用改装调整负热膨胀 (NTE) 来修改金属有机框架 (MOF). 将TCNQ引入Cu3BTC2框架改变了NTE的行为,展示了MOF属性控制的新方法.
科学领域:
- 材料科学
- 化学学
- 固态物理
背景情况:
- 金属有机框架 (MOF) 为结构与性能关系研究提供了一个模块化平台.
- 负热膨胀 (NTE) 是MOF的一个显著现象,通常与低能量的集体运动有关.
- 控制NTE对于先进的材料应用至关重要.
研究的目的:
- 调查引入额外连接 (改装) 对MOF的格子动态和NTE行为的影响.
- 展示一种在MOF中实验性调节NTE的方法.
- 探索对具有开放金属站点的MOF进行改装的一般适用性.
主要方法:
- 用TCNQ (7,7,8,8-四基诺二甲) 改装原型MOF Cu3BTC2 (HKUST-1).
- 通过变化 TCNQ 负载对 NTE 行为的实验性描述.
- 计算机建模和远红外光谱测试以确认框架的硬化.
主要成果:
- 调整体积热膨胀系数 (αV) 从 -15.3 × 10−6 K−1 (Cu3BTC2) 到 -8.4 × 10−6 K−1 (1.0TCNQ@Cu3BTC2).
- 证实了TCNQ负载和框架硬之间的相关性.
- 确认由于额外的网络连接而改变了格子动态.
结论:
- 改装是一种有效的策略,可以实验性地访问和修改MOF中的格子动态.
- 这种方法可以微调MOF中的NTE行为.
- 改装方法广泛适用于具有开放金属站点的MOF,扩大其设计可能性.
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