Rapid Fabrication And Catalytic Properties Of Nanoscale Metal-Organic Framework Meterials

Metal-organic frameworks (MOFs) are a new class of multifunctional porous crystalline materials, have attracted much potential applications in gas storage, selectivity adsorption and separation, magnetic materials, heterogeneous catalysis and optics, due to their intriguing structural motifs, structural diversity, tailor-made materials. To date a more efficient, simple and facile synthetic approaches to porous MOFs have attracted significant research for its many attractive applications.Generally, a number of synthesis methods, such as slow diffusion techniques, electrical heating, hydrothermal, and solvothermal methods, have been applied to the synthesized of NMOFs. In this paper, we describe a facile and environmentally friendly synthetic strategy to NMOFs by ultrasonic and microwave irradiation. Furthermore, we present the opportunity of NMOFs in the selective oxidation of organic compounds and photodegradation of industrial organic pollutants with high recycling rate. The main contents of this thesis are as follows:1. Nanocrystals of one-dimensional (1-D) MOF, Cu(INA)24H2O (1) and three-dimensional (3-D) MOF,[Cu(INA)2·H2O]·2H2O (2)were synthesized using the ultrasonic method with Cu(NO3)2·3H2O and HINA at an ambient temperature and atmospheric pressure under different conditions, for short reaction times and high yields. The structures were confirmed by Fourier transform infrared spectroscopy (FT-IR), elemental analysis and powder X-ray diffraction (XRD) patterns. In addition, Transmission electron microscopy (TEM) images of1and2reveal that size and shape of nanocrystals can be tuned by varying the reaction time. The nanocrystal of1can be selective catalytic oxidation of Rhodaming B (RhB) in the buffer solution of HAc-NaAc (oxidant:H2O2), and the nanocrystal of2can be selective catalytic oxidation of benzyl alcohol to benzaldehyde in the mixture solution of acetonitrile and water(oxidant:O2). The effects of reaction temperature, PH, the amount of catalyst, the amount of hydrogen peroxide (H2O2) and the air flow have been comprehensive investigated, and the mechanism of the catalytic reaction have been discussed in some detail. 2. A one-dimensional (1-D) metal-organic framework (MOF),[Co(INA)2(H2O)4](3), was synthesized by using ultrasonic method with cobalt acetate and isonicotinic acid. The structure was confirmed by FT-IR and XRD. Compared with hydrothermal synthesis of the same compounds, the results indicated that the nanocrystals of3were synthesized successfully. Scanning electron microscopy (SEM) images of3reveal that the size and shape of nanocrystals can be tuned by varying the reaction time. The nanocrystals of3can be selective catalytic degradate of RhB. The results indicated that the nanocrystals of3exhibit higher catalytic activity compared with titanium dioxide (TiO2) for the selective catalytic oxidation of RhB.3. Film of three-dimensional (3-D) MOF,[Zn3(BTC)2(H2O)2]-2H2O (4) was synthesized using a novel microwave method with Znic and H3BTC, for highly efficient. The structure was confirmed by FT-IR and XRD. The results indicated that the film of sample4was synthesized successfully, and indicated that microwave synthesis is a highly efficient method. In addition, transmission electron microscopy (TEM) images of4reveal that the size and shape of film can be tuned by varying the reaction time. We found that4exhibited highly photocatalytic activity for MB dye decolorization under UV-visible irradiation. The addition of electron accepors in the MB aqueous solution great enhanced the photocatalytic performances of4photocatalyst.