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This article is committed to the structure and properties of metal - organic frameworks (metal-organic frameworks, MOF). The aim of crystal engineering principles, rational choice of the central metal ion, aromatic carboxylic acids and heterocyclic bidentate bridging ligands build with multi-dimensional structure of MOF and study their structure, fluorescence and photocatalytic properties. The first chapter gives an overview of the basic concepts of the MOF, the research progress and topics related MOF, and the significance of the subject topics. The second chapter discusses three new MOF, obtained under hydrothermal conditions [Cd 3 (5-NO 2 -BDCs) 2 ( 5-NO 2 -bdcH) 2 (4,4 '-bpyo) 2 ] n (MOF1) (5-NO 2 -bdcH 2 = 5-nitro-1 ,3-benzenedicarboxylic acid; 4,4 '-bpyo = 4,4'-bipyridine-N, N'-dioxide), [Mn (5-NO 2 -bdc) (bbim)] n (MOF 2) (bhim = 1,1 '- (1, 2 -bdcH) the 4-butanediyl) bis (benzimidazole)) and {[Gd (5-NO 2 -bdc) (5-NO (H 2 < / sub> O) 2 ] (4,4 '-bpyo) 0.5 } n (MOF 3), and its structure characterization. The single-crystal X-ray diffraction studies show that: MOF 1 is centrosymmetric trinuclear cluster [of Cd 3 (COO) 4 O 2 ] SBU (secondary building units) NaCl-type topology. MOF 2 is a dual-metal clusters [Mn 2 (COO) of 2 ] SBU CsCl type topology, which is also the first to contain cis bbim bridge the MOF. MOF 3 is a dual-core cluster [Gd 2 (COO) 2 ] SBU assembly 2D (twodimensional) layer, while the 2D layer with 4,4 '-bpyo hydrogen bonds weak interaction further build the 3D (threedimensional) supramolecular framework. TG (thermal gravity) is higher than MOF: MOF and stability. Solid fluorescence spectra show that: the MOF the fluorescence emission at 410 and 429 nm, and derived from the ligand 4,4 'inner-bpyo is π-π * transitions. In addition, key research 4f Area metal Gd ion MOF heterogeneous systems, organic dyes - reactive brilliant red X3B (reactive brilliant red X3B) of photocatalytic degradation properties, reaction kinetics and mechanism. The study showed that: the ultraviolet and visible light irradiation, the degradation rate constants of X3B 0.1022 and 0.0138 h , -1 , corresponding quasi-first-order kinetics equation. TBA (tert.-butyl alcohol) do-OH radical quencher system, UV irradiation, the reaction rate constant for 0.0347h -1 decreased infer the possible reaction The mechanism of · OH radical oxidation activity extremely offensive X3B and its oxidation to complete the photocatalytic process. The PXRD results prove that in the degradation process, the catalyst MOF 3 has a high stability, and its body frame before and after the photocatalytic unchanged. The above shows that the MOF 3 has potential applications in photocatalytic treatment of organic dye pollutant in water. The third chapter discusses the hydrothermal conditions to obtain the six have not been reported MOF [the Cu (BDCs) (bimb)] the n (MOF) (1,4-bdcH 2 < / sub> = 1,4-benzenedicarboxylate; bimb = 4,4 '-bis (1-Imidazolyl) biphenyl), [M 3 (btc) 2 (bimb) 2 · (H 2 O) x ] n (M = Cu, x = 3 (MoF5); M = Mn (MOF6), Co (MOF 7), Cd (MOF 8), x = 4) (1,3,5-btcH 3 = 1,3,5-benzenetricarboxylate) and [ The single crystal X-ray diffraction studies show that: MOF 4 is formed by three separate the simple cubic monolayer network interpenetration 3D framework; MOF 5-8 (4,4,4) connected to isomorphism 3D framework; MOF 9 (3,4) connected to the 2D layer, while the 2D layer with bimb / btcH - of the CH group, and a carboxyl group on the oxygen atom in the ligand is further formed by hydrogen 3D Supramolecule framework. The TG: studies have shown that the MOF 4 and 9 stability than the MOF 5-8. The solid-state fluorescence spectra: the MOF fluorescence emission of 8 and 9, respectively, at 356 and 385 nm, and 358 and 388 nm, derived from the ligand the 1,3,5-btcH 3 the π in * < / sup>-n transition. In addition, focus on the isomorphism MOF 6 seven pairs X3B of, Photocatalytic degradation of performance, reaction kinetics and reaction mechanism. The results show that: the ultraviolet and visible light irradiation, the MOF 6 X3B the photocatalytic degradation rate constants were 0.1084 and 0.0727 h , -1 ;, MOF 7 on X3B the photocatalytic degradation rate constants were 0.2644 and 0.1348 h -1 , four data corresponding quasi-first-order kinetics reaction equation. In the catalytic process, MOF, 6 and 7 the performance of the high photocatalytic activity, the MOF 7 photocatalytic efficiency was significantly higher than the MOF. TBA, introduced in the reaction system, the rate of degradation is significantly reduced, to infer the high oxidation activity · OH radical through offensive X3B and its oxidation to accomplish the photocatalytic reaction, consistent with MOF3 The degradation mechanism. According to the molecular orbital theory, the ligand to metal charge transfer (LMCT) is a molecule of the electron from the highest occupied molecular orbital (HOMO) to the lowest unoccupied molecular orbital (LUMO) of transitions. Solid diffuse reflectance spectra show that: the MOF 6 and 7 the LMCT respectively 307 (262) and 333 (265) nm, thereby determining the band gap of the MOF 6 and 7, respectively, 4.04 and 3.72 eV. That MOF 6 energy band gap greater than MOF 7 energy band gap can be inferred MOF 7 of X3B photocatalytic degradation rate is greater than MOF6, inference consistent with the experimental results. MOF 6 and 7 catalyst activity difference with two MOF central metal ion different. The PXRD results demonstrate body frame 6 and 7, before and after the photocatalytic MOF unchanged. Above show that MOF 6 and 7 has potential applications in photocatalytic treatment of organic dyes in water pollutants. In the fourth chapter of the research done by a simple summary of the proposed the innovation point and MOF do photocatalyst prospect.
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