| Utilizing the corresponding principles and strategies of molecular design in the kingdom of crystal engineering, designing and assembling metal-organic frameworks crystalline materials with diversified networks, and studying their properties such as luminescence, magnetism, selective gas adsorption, separation and storage, selective catalysis, chemical sensors ect., is the foundational research themes of chemistry, physics, life sciences, materials and other intersectant fields. How to explore the nature of metal-organic frameworks crystalline materials at the molecular level, and applied them to design and synthesize metal-organic frameworks crystalline materials possessing specific structures and physicochemical properties, further achieve controllable configurations and properties, is significant theme in this field.In this contribution, selected semirigid V-shaped aromatic carboxylic acids, symmetrical or unsymmetrical, isomeric aromatic carboxylic acids as the basal component, designed and synthesized four series of twenty-eight metal-organic carboxylates frameworks crystalline materials, the structures of series of crystalline materials were analyzed and characterized by spectrum and thermal stabilities, choosed partial series of metal-organic frameworks crystalline materials, investigated their capabilities on photocatalysis and gas sensing and summarized the regulation. This work includes four chapters.Chapter1gives an introduction of the research progress, characteristic analysis, classification and potential functions in the field of material science of metal-organic frameworks crystalline materials. Moreover, the aim of selective theme and obtained results of this research work have been concluded.In chapter2, firstly, the synthetic strategies of metal-organic frameworks crystalline materials were discussed and summarized, secondly, used different organic carboxylic acids as the structural blocks, transitional metals, rare earths metal ions as the centers, attempted different synthetic methods, new twenty-eight metal-organic frameworks crystalline materials were obtained. And the detailed synthetic process of the different series of metal-organic carboxylates frameworks crystalline materials were described and summarized briefly.In chapter3, first of all, different series of metal-organic carboxylates frameworks crystalline materials were characterized by X-ray diffraction. The results were as follows:crystalline materials1was a three dimensional (3D) twofold6-connected pcu net topology containing binuclear wheel-propeller [Zn2(COO)4] secondary-building units(SBUs),4was a3D6-connected sxd net topology containing [Zn5(η2-O)2(μ2-η1:η1-CO2)]2-pentanuclear cores,5a and5b was a pair of genuine polymeric isomer, which exhibits3D (3,4)-connected net topology and3D (3,4)-connected twofold net topology,6was a3D (3,4)-connected net topology different from5,11was a3D8-connected self-penetrated net topology containing [PbⅡ6(μ4-O2-)2]8+clusters,12was a3D (4,5)-connected net topology containing ID Pb-O-Pb rod-shaped SBUs,23was a3D (3,5)-connected hms net topology,26was a3D (3,4,5,6,7)-connected net topology,27was a3D (4,5)-connected net topology different from12,3,8.22were all a2D44-sql net topology,25was a2D layer structure containg1D open tunnels,20and21was a pair of heterogenous isomorphs, which exhibit2D layer structures containing hetero-chiral alternate helical chain,2,9,10,13,14and19were diverse conformational1D chain structures,7and16were0D binuclear structures, in which the hydrogen bonds or stacking interaction between aromatic rings extended these low-dimensional structures into the supramolecular architectures with different network,15,17and18were isomeric with1,3and5b, respectively, so these structures were not discussed and their properties were only characterized. Morerover, the solid fluorescent spectrum of1-8,11,12,24-27, the variable temperature magnetic susceptibility of16,17,18and19as well as the thermogravimetric analysis of1-12,18,24-27were tested, According to the testing result, the relationship between the structure and functions of the above-mentioned crystalline materials were discussed.In chapter4, firstly, the applications of the metal-organic frameworks crystalline materials in the field of photocatalysis and chemical sensors were summarized. Secondly, choosing Zn(Ⅱ)/Cu(Ⅱ) partial series of metal-organic carboxylates frameworks crystalline materials1,4,6and15,16,17, using methylic orange, Congo red and Rhodamine B as the organic pollutants, studied the photocatalysis degradation under the condition of simulated visible light as xenon bulb. The results indicated two series of crystalline materials exhibited incoordinately degradation effect on three pollutants, Under the same testing conditions, the degradation ratio of Congo red and Rhodamine B were95.7%and91.0%using the crystalline material4as the photocatalyst, the degradation ratio of Congo red and Rhodamine B were91.8%and89.5%using the crystalline material1as the photocatalyst, the degradation ratio of Rhodamine B were95.4%using the crystalline material16as the photocatalyst, so these kind of crystalline materials possess potential photocatalysis materials. Thirdly, selecting Cu(Ⅱ)/Co(Ⅱ) partial series of metal-organic carboxylates frameworks crystalline materials15,16, and18, and easy volatility organic solvents with different polarity, tested the gas sensing, we found that the components of crystalline materials15and18exhibited positive response in the saturated methanol steam, the component15showed high sensitivity and bad linearity, but the component18displayed moderate sensitivity and excellent linearity in the range of wide concentration, the results might provide experimental attestation for application of crystalline materials on chemical sensors.In a word, the obtained outcome of this dissertation not only enriches the contents of crystal engineering and materials chemistry, but also provides a new idea and consulting effect to design and prepare metal-organic carboxylates frameworks crystalline materials with diverse networks and especial properties.
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