| As one of the research fields of coordination chemistry,polyoxometalates have potential application value and significance in the fields of electrochemistry,catalysis and preparation of nanomaterials.In recent years,the research of polyoxometalates in waste degradation and energy storage has attracted extensive attention of chemists.This paper utilizes the salt or oxides as starting material to synthesize 9 kinds of new arsenotungstates based polyanions through simple one-step hydrothermal synthesis,selecting different transition-metal and organic ligands.Additionally,the crystal structures are characterized by X-ray single-crystal diffraction,elemental analysis,IR,TG and XRD,which identifying the formula of Compounds 1-9 as follows:[Hbimb]2[HAsW12O40]?1?[Hbpy]2[HAsW12O40]?2?[Ag?bpy?3]2[HAsW12O40]?3?[CuI?diz?2]2[{CuI?diz?2}(AsW12O40)]?4?[Cu?Himi?4][?pz?0.5{Cu3Na3(AsW9O33)2}]?Hpz?3·H2O?5?[Hbima]6[As2W18O62]?6?[Hbiz]6[As2W18O62]?7?[Himi]4[H2As2W18O62]·4H2O?8?[CuI?imi?2]6[As2W18O62]·2H2O?9?[bimb=1,4-bis?benzoimidazo-1-ly?benzene;bpy=4,4-bipyridine;bpy=2,2-bipyridine;diz=1,2-Diazole;imi=imidazole;pz=pyrazine;bima=2-Aminobenzimidazole;biz=Benzimidazole]X-ray single-crystal diffraction analysis reveals that Compounds 1-4 contains the same polyoxoanions[HxAsW12O40]?3-x?-:Supramolecular structure of Compound 1,2was composed of free organic ligands[Hbimb]+,[Hbpy]+and polyoxoanions[HAsW12O40]2-,respectively;In Compound 3,Ag ion and bpy coordinated to form metal organic complex,which is free in[HAsW12O40]2-outside.Compounds 1-3 form1D,2D and 3D supramolecular structures through hydrogen bonds;In Compound 4organic ligand diz and Cu ion coordinated to form[CuI?diz?2]+chain complex,and each[AsW12O40]3-is connected with[CuI?diz?2]+by Cu-O bond to form double support 1D chain compound.Basic frameworks of 5 is constructed from sandwich-type[?pz?0.5{Cu3Na3(AsW9O33)2}]anions,[Cu?Himi?4]complex,free protonated pz ligands and water molecule.The transition metal ions Cu2+and Na+in the central belt connect alternately in an edge-sharing mode forming a hexa-nuclear ring.pz ligand and[Cu?Himi?4]as bridge connect to{Cu3Na3(AsW9O33)2}fragments,respectively,which forms a enormous ten-members ring,then leading to constitute a novel 2D ABAB arrangement layer structure.Compounds 6-9 contain Wells-Dawson polyoxoanion[HxAs2W18O62]?6-x?-:The structural units of Compounds 6 and 7 contain polyoxoanion[As2W18O62]6-and six free organic ligands.The difference of Compounds 6 and 7 is that the organic ligand in Compound 6 is bima,while the organic ligand in Compound 7 is biz.Compound 8 contains four free organic ligands[Himi]+,polyoxoanion[H2As2W18O62]4-,and four water molecules;Compound 9 contains six free metal organic complexes[CuI?imi?2]+,polyoxoanion[As2W18O62]6-,and two water molecules,two adjacent polyoxoanions[As2W18O62]6-and two parallel complexes[CuI?imi?2]+form the 1D structure through hydrogen bonding.All four compounds are supramolecular structures.The electrochemical test of Compounds 1-9 showed that all the compounds exhibit the good cyclic voltammetry stability and electrocatalytic activity upon the reduction of H2O2 also has been studied.In addition,Compounds 1-9 shows excellent photocatalytic activity for the degradation of MB and RhB dye under UV irradiation,the photocatalytic decomposition rates were 90%of MB and 85%of RhB,indicating that the synthesized compound were a kind of better photocatalyst. |
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