Syntheses, Structures And Properties Of Some Lacunary Polyoxometalates And Transitional Metal Tungstosilicates

Since 2007, the design and synthesis of transition-metal-substitutedpolyoxometalates (TMSPs) based on lacunary precursors derived from Kegginpolyanions are of great interest owing to not only their intriguing structuralframeworks but also potential applications in catalysis, medicines, materialsand electronic properties etc. In this thesis, some aberrant or lacunary polyoxometalates (1-6), aone-dimensional chain-like structure of silicotungstate cluster compound (7)and four novel organic-inorganic hybrid compounds (8-11) have beensynthesized on the basis of hydrothermal technique and structurallycharacterized by elemental analyses, IR and single crystal X-ray diffractions.The thermal stabilities, fluorescent properties, electrochemical behavior andmagnetism activity of a part of the compounds have been studied. Compounds1,2,3,5,6,7,8,9�'�11 were used as a bulk-modifier to fabricate athree-dimensional chemically modified carbon paste electrode (CPE) by directmixing. The electrochemical behavior of the solid particles dispersed in theCPE in acidic aqueous solution is characterized by cyclic voltammetry. Theirchemical formulas are listed as follows:{[H4Si2WⅡW22ⅥO78][NiⅡ(C4H13N3)2]3(H3O)4}·4H2O (1),[CuⅠ(C2H8N2)2(H2O)][CuⅠ(C2H8N2)2][CuⅠ(C2H8N2)(H2O)2][H3SiCuⅡW11ⅥO39]·6H2O(2),{[Si2W4ⅤW20ⅥO78(CuⅠ/Ⅱ(C2N2H8)2)2)][CuI(C2N2H8)2]2[CuⅠ/Ⅱ(C2N2H8)2(H2O)]2}·8H2O (3),[NiⅢ(C2H8N2)2](H3O)3{[NiⅡ(C2H8N2)(H2O)3]2[NiⅡ(C2H9N2)]2[H4Ge2Ni2ⅡW18ⅥO68]}·6H2O(4),{[Co4Ge2W18070]·7(C12H14N2)·2(H3O)}·6H2O(5),{[NiⅡ6(μ3-OH)3(en)3(H2O)6](α-SiW9O34)}NiⅠ0.5(en)·3.5H2O(6),[(H8NaKW12ⅥO45) (C2H10N2)4]·4H2O (7), H4[SiW12ⅥO40]·8 (C12H12N2)·4H2O(8),[NiⅡ(C3H10N2)2](OH)2[NiⅡ(C3H10N2)2(H2O)2]2[SiW12ⅥO40]·H2O (9),{[NiⅡ(1,10-phen)3] [NiⅡ(en)2][SiWⅤ2W10Ⅵ039]}·en·1.5H2O (10)[VⅡ(1,10-phen)3]2 [SiW12ⅥO40]·C4H10N2 (11)...