Synthesis And Properties Of The POM-Inorganic Organic Hybrid Materials Constructed By Transition Metal And Rigid/flexible N-donor Organic Ligands

In this thesis, we synthesized eighteen new POM- inorganic organic hybrid materials constructed by transition metal, Rigid/Flexible N-donor organic ligands and polymolybdate building blocks under hydrothermal condition. The eighteen new POMinorganic organic hybrid materials have been structurally characterized by elemental analyses, IR, XPRD, TG, XPS and single crystal X-ray diffractions. The photoluminescence properties, electrochemical properties, photocatalysis properties, magnetic properties of these compounds have been studied. Through investigate of synthesis conditions, types of transition metal ions, organic ligand structure and p H value on the influence of compound structures, explore the relationship between the structures and properties of new materials, enrich the synthesis chemistry of polymolybdate. To provide theoretical and experimental basis of oriented synthesis the new functional materials of polymolybdate.1. Eight new inorganic organic hybrid materials have been prepared and characterized by using isopolyoxometalate building blocks with the different Rigid/Flexible N-donor organic ligands:[Cu8L8(β-Mo8O26)( γ-Mo8O26)]·3H2O(1)[Ag4L4(γ-Mo8O26)]·2H2O(2)[Ni2L2(γ-Mo8O26)(H2O)8]·3H2O(3)[Co2L4(Co2Mo10O34)]·6H2O(4)[Ni4H4L8(Mo2O7)2(Mo4O14)(H2O)2](Mo2O8)·11H2O(5)[Cu4(btb)10(γ-Mo8O26)2]·8H2O(6)[Zn2(btb)3(γ-Mo8O26)(H2O)4][Zn2(btb)(H2O)4]?6H2O(7)[Cu4(btx)4(β-Mo8O26)](8) Compound 1 represents the first example with two types of 2D�'2D parallel interpenetration frameworks, one has the(β-Mo8O26)4- isomer, and the other has the(γ-Mo8O26)4- isomer. Furthermore, the two 2D networks in one 2D�'2D parallel interpenetration framework are different. The 2, 4, 5-tri(4-pyridyl)- imidazole(L) is for the first time introduced into the POM system in compounds 1-5. The(Co2Mo10O34)4- polyanion in compound 4 has not been reported. Compounds 3, 6, 7 are rare octamolybdates modified by organic molecules through the Mo-N bonds. The optical band gaps of 1-8 have shown that these compounds are potential semiconductor materials. The luminescence behaviors of compounds 1, 2, and 7 reveal these compounds may be good optical material.2. Six new inorganic organic hybrid materials have been prepared and characterized by using Keggin anions building blocks with the different Rigid/Flexible N-donor organic ligands:[Cu H3L2(Ge Mo12O40)]?2H2O(9)[Cu H3L2(Si Mo12O40)]?2H2O(10)[Co2(btp)3(Ge Mo12O40)](11)[Cu4(bte)4(Ge Mo12O40)](12)[Ag4(btp)2(PMo12O40)](13)[Ag4(btb)2(PMo12O40)](14)Compounds 9 and 10 are the first time to use the L ligand to synthesis the Keggin-type polyoxometalate-based inorganic–organic hybrids. The two compounds possess the left- and right-handed helical chains and the adjacent 2D layers possessing the different handedness of helical chains are linked alternately through hydrogen bonds to form a 3D supramolecular network. Compounds 11-14 are synthesis by three different lengths of flexible ligands. Thereinto, compounds 12 and 13 are synthesis by the same flexible ligand btp and different transition metals. Compound 12 is 3D framework with 2-fold interpenetrating pcu topological net. Compound 13 is 3D supramolecular structure which constructed from 1D chains and polyanions through hydrogen bonds. Btb in compound 14 acts as tetradentate ligand extended the structure into 3D structure. The luminescence behaviors of compound 9 and 10 reveal that these compounds may be good optical materials, and can be used as a photocatalyst degradation of MB, used as electrocatalyst degradation of nitrite. The optical band gaps of compounds 11-14 indicate that the compounds 11-14 are potential semiconductive materials.3. Four bimolybdenum-capped tetra-NiII sandwich-type molybdogermanates have been hydrothermally prepared and characterized by using different Rigid/Flexible N-donor organic ligands:(H8L4) {[Ni4(H2O) 2] [B-α-Ge Mo9O34]2(Mo O2)2} ·7H2O(15)[Ni2H4L4(H2O) 2] {[Ni4(H2O) 2] [B-α-Ge Mo9O34]2(Mo O2)2} ·12H2O(16)[H8(bix)4]{[Ni4(H2O) 2] [B-α-Ge Mo9O34]2(Mo O2)2} ·4H2O(17)[H8(bbi)4]{[Ni4(H2O) 2] [B-α-Ge Mo9O34]2(Mo O2)2} ·4H2O(18)The four compounds contain a new bimolybdenum-capped sandwich-type heteropolymolybdate anion, [Ni4(H2O)2{B-α-Ge Mo9O34(Mo O2)}2]8-. The compounds 15、17、18 are 0-D supramolecular compounds and the supramolecular architecture of compound 16 is the rare 2D inorganic–organic composite structures constructed from sandwich-type TMSPs. The 15-CPE and 16-CPE present electrocatalytic activity for the reduction of nitrite.