Microporous Metal-Organic Framework Materials for Gas Adsorption and Separation

Gas separation is a very important industrial process for manufacturing chemicals, fuels, plastics and polymers but energy-intensive through the conventional cryogenic distillations. Adsorption based gas separation by porous materials can potentially address the energy-efficient gas separation economy. As a novel type of crystalline porous material, MOFs, also known as porous coordination polymers, have been demonstrated for their promise in addressing important gas separations. Among numerous structures, the microporous and ultra-microporous MOFs are of interest owing to their outperforming in specific and selective molecular recognition. Several strategies have been utilized to enhance selective gas separation in MOFs, including the fabrication of MOFs with binding sites such as open metal sites. Another approach is adjusting pore size for a sieving effect, which is usually achieved by ligand length modulation. The incorporation of fine-tunable pore size and open metal sites onto the pore surface, leading to multifunctionality, may be a rational combination to enhance the gas separation performance. In this dissertation, a series of microporous metal−organic framework (MOF) materials ([Cu(BDC2Br)(H2O)]·DMF, [Cu(BDC-Br)(H2O)0.5(DMF)2.5], [Cu(BDC-NO2)(DMF)], and [Cu(hfipbb)(H2hfipbb0.5)]) have been proposed with multifunctionality to study their potential application in gas adsorption and separation.