Trapping Guests within a Nanoporous Metal-Organic Framework through Pressure-Induced Amorphization
Trapping Guests within a Nanoporous Metal-Organic Framework through Pressure-Induced Amorphization
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DOI：
10.1021/ja2085096
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发表时间：
2011-11-23
影响因子：
15
通讯作者：
Nenoff, Tina M.
中科院分区：
文献类型：
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作者：
Chapman, Karena W.;Sava, Dorina F.;Nenoff, Tina M.
从纳米多孔金属有机框架（MOF）内的客体物种的释放已被抑制在施加压力下的客体负载的框架结构的非晶化。热重分析表明，通过在吸附分子I-2（核能生产的危险放射性副产物）之后使ZIF-8非晶化，框架中的孔隙充分变形以动力学地捕获I-2并改善I-2保留。对分布函数（PDF）分析表明，俘获I-2的局部结构在骨架非晶化后基本保持不变，并且对于空骨架和负载客骨架，非晶化在相同条件下发生。实现这种解吸变化所需的低的、可接近的压力范围比传统吸附剂如沸石低得多，为新的分子捕获、临时储存或控释应用开辟了可能性。
The release of guest species from within a nanoporous metal-organic framework (MOF) has been inhibited by amorphization of the guest-loaded framework structure under applied pressure. Thermogravimetric analyses have shown that by amorphizing ZIF-8 following sorption of molecular I-2, hazardous radiological byproduct of nuclear energy production, the pore apertures in the framework are sufficiently distorted to kinetically trap I-2 and improve I-2 retention. Pair distribution function (PDF) analysis indicates that the local structure of the captive I-2 remains essentially unchanged upon amorphization of the framework, with the amorphization occurring under the same conditions for the vacant and guest-loaded framework. The low, accessible pressure range needed to effect this change in desorption is much lower than in tradition sorbents such as zeolites, opening the possibility for new molecular capture, interim storage, or controlled release applications.