传压介质对不同金属离子配位MOFs材料的高压行为影响的研究

As a new class of porous materials, Metal-organic framework (MOFs) materials are comprised of ordered network formed from organic electron donor linkers and metal cations. As the well known porous materials Zeolite, MOFs have high surface areas and open frameworks but more flexible pore size and functionality. So far, MOFs have been reported having many important technological, industrial, and environmental applications in areas such as molecular sensing, strategic gas storage/separation, and drug delivery etc. In addition, different from Zeolite, MOFs have organic linkers in their structures, thus their pore size and functionality are more flexible and tunable, which makes MOFs one of the star porous materials that attract increasing attentions in many fields, for instance, high pressure science. .Pressure can significantly alter the interatomic distances and thus the nature of intermolecular interactions, molecular configurations, crystal structures, and stabilities of solids. Consequently, it is usually used as a powerful tool to tune structures of solids. The well documented structural complexities of MOFs can be expected to yield unprecedented pressure-induced phenomena, with further potential for coupling of the host-guest properties afforded by their open structures and small molecule pressure-transmitting media (PTM) often used in high-pressure science. Moreover, compared to traditional solid state materials, structures and functionality of MOFs are more sensitive to pressure, which means modification of structures can occur at less extreme pressure that could be routinely encountered in practical applications. Therefore, we proposed a high pressure study of Basolite MOFs with different metal cations. This project will focus on studying high pressure of pure samples with/without PTM in term of phase transitions, pressure induced amorphization, compressibility, and stability, as well as search for pressure induced pore size and structural modification. Effect of guest molecules on their high pressure behavior as well as host-and-guest molecules interaction will also be addressed. By finishing this project, we will get a better idea about high pressure behaviors of MOFs with/without PTM. Thence, this project could not only provide valuable information for understanding chemical absorption property of MOFs aiming for practical applications, but also useful for future high pressure studies on other porous materials especially those porous materials with similar structure. Moreover, this project could also shed light on pressure induced pore size and structural modifications for industrial application purposes. Finally, this project mainly relies on beamline 15U in Shanghai Synchrotron Radiation Facility. Thence, conducting this project is helpful to improve its performance in high pressure science, which will enhance its users’ experience in the future.

金属有机骨架是一种基于金属离子和有机电子给予体配位的多孔材料，比表面积高、孔径多样化，在分子传感器、气体存储/分离、药物载体方面有重要应用。MOFs的有机部分使其孔径大小及性能具有较高可塑性，在越来越多领域受到关注，如高压科学。已有的研究表明，MOFs复杂的结构使其对高压的反应不易预测，而开放的孔道可吸收高压实验中传压介质，是研究主客体化学的好样本。更重要的是，MOFs结构改变所需压强较低，使MOFs的高压研究更具实际意义。因此，本项目将研究三种不同金属离子配位的Basolite MOFs的高压行为、结构稳定性及金属配位离子和传压介质对其高压行为的影响。本项目将有助于进一步了解MOFs的结构稳定性以及与客体分子的相互作用，为研究其他多孔材料及开发相关工业应用提供重要的参考信息。本项目依附于中国科学院上海应用物理研究所上海光源的硬X射线微聚焦及应用线站，有助于积累该线站在高压衍射方面的经验。

金属有机骨架由于其比表面积高、孔径多样化，在分子传感器、气体存储/分离、药物载体方面有重要应用，已在越来越多领域受到关注。已有的研究表明，MOFs复杂的结构使其对高压的反应不易预测，而开放的孔道可吸收高压实验中传压介质，是研究主客体化学的好样本。因此，本项目通过利用同步辐射X射线衍射及振动光谱研究铜配位（Cu-MOFs）、锌配位（ZIF-8）和钴配位（ZIF-67）MOFs的高压行为、结构稳定性及金属配位离子和传压介质对其高压行为的影响。我们的研究揭示了MOFs材料中的残余水分子可以起到与传压介质相同的作用，传压介质对材料的稳定性有提高作用。对于同一材料，传压介质对其高压稳定性的影响与传压介质的分子大小相关。我们的研究还发现，金属离子的配位可影响材料的结构高压稳定性，而该影响与金属有机配体化学键的刚性有关。本项目将有助于进一步了解MOFs的结构稳定性以及与客体分子的相互作用，为研究其他多孔材料及开发相关工业应用提供重要的参考信息。