高稳定疏水金属有机框架的构筑与吸附分离性质研究

MOF材料被认为是一类具有广阔应用前景的新兴多孔材料。实际应用中MOF材料的水稳定性和水的竞争吸附问题近年来受到越来越多的关注。众多吸附分离体系中都含有不同程度的水，MOF水稳定性差势必限制其应用，水的竞争吸附也可能影响其实用性。例如，当MOF材料应用于吸附去除甲醛、苯、氨等室内空气有害物时，室内空气中不可避免地含有水蒸汽，且浓度明显高于这些有害物。如果水被优先吸附到MOF孔道中，MOF材料对有害物的吸附去除能力可能减弱甚至丧失。本项目拟采用配体设计和后合成修饰两种思路构筑基于Zr6(µ3-O)4(µ3-OH)4(-CO2)12，[Fe2M(μ3-O)(-CO2)6]（M代表系列金属离子）等稳固型结构基元的疏水性MOF，探索MOF疏水性的影响因素和调节方法，研究MOF的疏水性对其实际吸附分离的影响，并归纳总结规律，为疏水性和水稳定性兼具型MOF材料的设计合成与应用提供实验基础和理论指导。

Metal-organic frameworks (MOFs) are a class of promising porous materials with application potential in many fields due to many advantages, such as structural variety and designability. During the past many years, one research hotspot for MOFs is to improve their structural stability against water. In the last few years, much studies have also been carried out to investigate the effects of water on application performance of MOFs. Water may react with MOFs, resulting in degradation of their crystalline and porous structures, and loss of their functions. On the other hand, competitive sorption between water and other adsorbates may significantly limit practical applicability of MOFs in some applications. For example, when MOFs are utilized as adsorbents to remove indoor harmful substances like formaldehyde, benzene, ammonia etc., the indoor air must be more or less humid, and the concentration of water vapor in the air is always much higher than those of the harmful substances. If water is preferentially adsorbed by MOFs, their pores are occupied, and the capability of the MOFs to adsorb these harmful substances may reduce, even lose. In this proposal, we are planning to construct highly water stable and hydrophobic MOFs with some robust second building units, such as Zr6(µ3-O)4(µ3-OH)4(-CO2)12 and [Fe2M(μ3-O)(-CO2)6] (M = Fe2+, Co2+, Ni2+, Mn2+ or Zn2+), by two synthetic strategies, namely, ligand design and postsynthetic modification, quest the factors for hydrophobicity of MOFs and methods to tune the hydrophobicity, investigate the effects of hydrophobicity on the application performances of the MOFs, and generalize scientific laws as a guide for future research on the design, synthesis and application of water stable and hydrophobic MOFs.