| Polyoxometalates have extremely potentially important practical value and application prospects in many fields such as electrochemistry,electricity and photocatalysis,and the preparation of nano-level materials.Among them,the arsenic-tungsten-based polyacid is one of the most important components of the polyoxometalate,but the arsenic source required for the synthesis and preparation of such compounds is the more toxic organic arsenic or As2O3,so the current arsenic-tungsten-based polymetal There are few reports on oxo acid salt related compounds.In this paper,Na As O2 is used as the arsenic source,Na2WO4·2H2O is used as the tungsten source,and different transition metal salts and different types of organic ligands are used as the structural support.The hydrothermal method is used to synthesize 7 different arsenic-tungsten bases.Acid anion inorganic-organic hybrid compound.As followed:[Ag3（biim）3][AsW12O40]·4H2O（1）[Ag2（biim）2][HAsW12O40]（2）[Ag（diet）2]2[HAsW12O40]（3）[Cu（bpy）3][HAsW12O40]·2H2O（4）[Co（bpy）3]2[As2W18O62]（5）[Cu（pz）2]2[Cu2（pz）2][H2As2W18O62]·2H2O（6）[H2tib]2[H2As2W18O62]·3H2O（7）[biim=Di imidazole;diet=1,2-di（1H-imidazol-1-yl）ethane;bpy=2,2’-Bipyridine;Pz=pyrazine;tib=1,3,5-tris（1-imidazoly）benzen]X-rays show that compound 1 contains a Keggin type polyanion[AsW12O40]3-,three Ag ions in the crystal structure alternately coordinate with the organic ligand biim to form[Ag3（biim）3]3+chain ligand ions,Each[AsW12O40]3-is connected with the complex ion through Ag-O bond to form 1D chain compound;compound 2-4 contains Keggin type polyanion[HAsW12O40]2-,two in 2 in the structure of the compound Ag ion and two organic ligands biim form[Ag2（biim）2]2+double coordination complex ion,each[AsW12O40]3-is connected with the complex ion through Ag-O bond to form 1D chain compound;compound 3,4 are metal-organic complexes formed by the coordination of Ag ion and organic ligand diet and Cu ion and organic ligand bpy coordination.They are respectively free in the periphery of[HAsW12O40]2-,and these two compounds are formed by hydrogen bonding.1D,2D and 3D supramolecular structures;compound 5 contains Dawson-type polyanion[As2W18O62]6-structure,Co ions coordinate with bpy to form a six-coordinated complex,which is free on the outside of[As2W18O62]6-to form Typical supramolecular compounds;compounds 6-7all contain Dawson-type polyanion[H2As2W18O62]4-structural unit.In compound 6,there are two coordination modes between pz and Cu I ion,namely two[Cu（pz）2]+and a[Cu2（pz）2]2+are respectively placed outside the polyanion[H2As2W18O62]4-,connected by Cu I-O bond,and each[Cu2（pz）2]2+bridges two Adjacent polyanion[H2As2W18O62]4-to form the 1D chain compound;compound 7 is a supramolecular compound composed of two free[H2tib]2+organic ligands and polyacid anion[H2As2W18O62]4-.Relevant electrochemical tests were carried out on compounds 1-7.The relevant results showed that all 7 compounds have high-quality cyclic voltammetric stability.At the same time,experiments on the electrocatalytic properties of the above compounds have been carried out,and the results show that they all have good electrocatalytic activity for H2O2.In addition,the photocatalytic properties of 1-7 compounds were studied.The degradation of MB and Rh B by 1-7 showed excellent photocatalytic performance,and the degradation rate of both exceeded 87%.The results showed that the 7 compounds All have good photocatalytic activity. |
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