The Synthesis,Characterization And Properties Of Three Dimensional Frameworks Structures Based On Polyoxovanadates

Four novel purely inorganic or inorganic-organic hybrid materials based polyoxovanadates were successfully synthesized under the hydrothermal condition. In addition, their structure characteristic and properties were studied.Two novel purely inorganic frameworks materials based on {PV₁₈} units and Mn linkers were synthesized under the hydrothermal condition,H₇[Mn₄?H₂O?₁₁V^IV₁₈O₄₂?PO₄?]·4H₂O?1? and[NH₄]₅H₆[Mn₂?H₂O?7V^IV₁₈O₄₂?PO₄?]·C₃H₁₀N₂·2H₂O?2?. The valence state of V centres in the polyanion of compound 1 and 2 were all in +4, which led to first time form the purely inorganic 3D frameworks based on heterobule. The reduced block units have led to {PV₁₈} with enough negative charges for accepting transition metals, the least block units in 1 and 2 have integrated 12 and 5 Mn ions, then the different 3D frameworks were generated. The removing the symmetry center or mirror in POM may produce a chiral skeleton, the flack parameter of 0.02?3? confirmed compound 2 with an absolute chiral configuration. It crystallized into chiral crystalline materials via chiral symmetry breaking.This is the first chiral material constructed from the reduced POVs, obtained from achiral precursors. In addition, the electrochemistry and electrocatalysis of compound 1 were studied.Two novel core-shell nanostructure models based on {PV₁₈} and Ni-organic anime units were successfully synthesized by hydrothermal technology,NH₄[Ni?dap?₂]₄[V₁₂^IVV₆^VO₄₂?PO₄?]·4H₂O?3? and NH₄[Ni?dap?₃]₄[V₁₂^IVV₆^VO₄₂?PO₄?]?4??dap = 1,2-diaminopropane?. In the assembled processes of 3 and 4, the amount of coordinate of Ni and Ni-dap unit both have effected on the forming of core-shell models.The spherical-shape structure [PV₁₈O₄6]^9- cluster was first time introduced into the core-shell nanostructures models, which offered the crystal status models for further understanding the essential properties and principles of core–shell nanostructures. The electrocatalytic study revealed that both of compound 3 and 4 process well electrocatalytic activity for reduction of H₂O₂ and oxidation of the NO₂^-.