| Metal-Organic Frameworks (MOFs) are a new class of porous material, which have extensive application prospect. This study is mainly focused on the synthesis, modification, activation, and application of MOFs materials. Three MOFs (Cu3(btc)2, ZIF-8, MIL-53) and a composite:CNT@[Cu3(btc)2] were synthesized by solvothermal method, microwave synthesis and centrifugation.The samples were systemically characterized by several analysis methods, such as X-ray powder diffraction, thermal gravity analysis, infrared spectra, transmission electron microscope and X-ray photoelectron spectroscopy. Results show that the incorporation of CNTs enhances the strength of the material and provides a route for removal of guest solvent molecules during activation, leading to a larger pore volume of CNT@[Cu3(btc)2]. Gas adsorption measurements show that the incorporation of CNTs in MOFs enhances the CO2and CH4adsorption capacities significantly. Compared to the unmodified Cu3(btc)2, the composite CNT@[Cu3(btc)2] shows CO2and CH4uptakes are increased by about102%and66.7%(298K,18bar), respectively.The samples of Cu3(btc)2, ZIF-8and MIL-53were activated by traditional volatile solvent (chloroform) replacement and supercritical CO2(Sc-CO2) drying method. Results demonstrate that the guest solvent retained in MOFs was removed effectively by Sc-CO2drying without collapse of the frameworks. And the samples activated by Sc-CO2show larger specific surface area and pore volume. Thus, Sc-CO2drying method is much better than volatile solvent (chloroform) replacement in activating MOFs.Dissolve4,4’-dipyridyldisulfide and cobalt ions in a mixed solvent of H2O and C2H5OH. After slow evaporation at low temperature, a new two-dimensional metal-organic framework was obtained. It was named Co-Dpds, and the crystal structure was determined as [Co(O)2(Dpds)2]n by X-ray crystallography. The open metal site formed by high-temperature dehydration is meaningful for gas storage and catalysis. |
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