Hydrothermal Syntheses And Characterizations Of Vanadate Crystalline Materials

Vanadates are a new type of material with unique molecular structure and excellent properties such as optical,magnetism,electrical and catalytic properties,which are a key material for new generation of lasers,vanadium batteries,magnetic information recorders and the others,so that researchers have an interest in their syntheses,structures and properties.In order to develop the potential application of new kind of vanadate materials,eleven new compounds have been synthesized and structurally characterized by IR,UV-vis,thermogravimetric analysis,powder X-ray diffraction,single crystal X-ray diffraction.The magnetism,luminescent,thermal stabilities,and photocatalysis of some compounds were further investigated.1.Vanadates: Five new vanadates,[Cu₄（biimpy）4(V₄O₁₂)]n·2H₂O（biimpy=2,6-bis（1-imdazoly）pyridine）（1）,[V₂O₂（H₂O）₂Cl₄（4,4′-bpy）3]（2）,[VOCl（2,2′-bpy）₂]Cl·2H₂O（3）,[V₂O₂（C₂O₄）]·5H₂O（4）,{VO₂[NH（CH₂COOH）₂]}（5）have been successfully made under hydrothermal conditions.Compound 1 provides the first example of 2-D heterometallic polymer based on the linkages of two types of1-D cuprous biimply chains and inorganic circle [V₄O₁₂]4-clusters.Compound 1shows good photocatalytic properties.In compound 2,the [V₂O₂（H₂O）₂Cl₄（4,4’-bpy）3]chain are connected via hydrogen bond to form a 3-D H-bonding network structure.Compound 3 consists of [VOCl（2,2’-bpy）₂]+cation and Cl-anion.Compound 4 and 5display a 1-D chain,which are further arranged in an parallel manner.2、Boron vanadates: Two new 3-D vanadoborates {[Cd（H₂O）₂]3V₁₂B₁₈O₅₄-（OH）6}·4H₃O·26H₂O（6）and [K6（H₂O）10Zn₄V₁₀B₃₂O₇₄（OH）10]·5H₂O（7）were prepared under hydrothermal conditions.The 3-D framework of compound 6 is constructed by the lingkages of [V₁₂B₁₈O₅₄（OH）6]10-clusters and [CdO6] octahedra,which displays new type of 3-D open-framework vanadoborate.Compound 7 contains[Zn₄V₁₀B₃₂O₇₄（OH）10]6-clusters and 2-D [K6O₃₅]n layers,which are interconnected to form another 3-D [K6（H₂O）10Zn₄V₁₀B₃₂O₇₄（OH）₁₀] architecture with 1-D tunnels filled with free H₂ O molecules.Compound 7 is the first example of 3-D vanadoborate framework based on quaternary vanadoborate [Zn₄V₁₀B₃₂O₇₄（OH）₁₀]6-cluster.Compounds 6 and 7 display good photocatalytic and magnetic properties.3.Imidazole coordination polymers: Four new imidazole coordination polymers[CuI₂Cl（μ5-L）]n（HL=1-tetrazole-4-imidazole-benzene）（8）,[CuI（L）]n（L = ethylisonicotinate）（9）,[Co₂（OH）Cl L₂]·3.5H₂O（HL=1-tetrazole-4-imidazole-benzene）（10）,[MnO₂L₂]（HL =1-tetrazole-4-imidazole-benzene）（11）have been successfully made under hydrothermal conditions.Compound 8 displays 3-D architecture built up from the linkages of rare [CuI₂Cl]+ cations and L-ligands.Its thermal stability,photoluminescent properties and density functional theory calculation were also studied.Compounds 9 displays 1-D chain with good photoluminescent properties.Compound 10 exhibits 3-D open framework based on the linkages inorganic[Co₄（OH）₄Cl₂] clusters and L ligands.Compound 11 exhibits a 1-D chain.