Synthesis And Catalytic Properties Of Polyoxometaiates Modified With Coordiation Compounds

Coordination compounds with good coordination ability，the rich various ofstructures, special catalytic oxidation property and molecular recognition ability, havebeen always researched as a hot field. Polyoxometalates have been widely used infunctional materials and catalysis, because of their strong acid, oxidoreduction property,structural versatility and so on. Therefore, the combination of coordination compoundsand polyoxometallates has significance of research and application.In this paper, some kinds of high catalytic activity of polyoxometallates modifiedby coordination compounds have been synthetize by chemical coprecipitation method:[Ru（2,2^′-bipy）₃]₃（PW₁2O₄0）₂（1）,[Ru（2,2^′-bipy）₃]₃（PMo₁2O₄0）₂（2）,[Ru（2,2^′-bipy）₃]₂（SiW12_O40）（3）,（CuC₁2H₃0N₆）₃（PW₁2O₄0）₂（4）,（CuC₁2H₃0N₆）₃（PMo₁2O₄0）₂（5）,（CuC₁2H₃0N₆）₂（SiW₁2O₄0）₂（6）,（NiC₁0H₂6N₆）₃（PW₁2O₄0）₂（7）.We discuss the composition and thermal stability of these compounds by thecharacterization of the element analysis, IR, XRD, BET surface area and TG. Thecatalytic properties have been researched in the degradation reaction of rhodamine B inwater solution.The main studies of this paper are as follows:（I） Compounds （1）,（2）,（3） are synthesized with ruthenium pyridine[Ru（2,2^′-bipy）₃]Cl₂and phosphotungstic acid, phosphomolybdic acid and silicotungstic acidrespectively. The element analysis and infrared spectroscopic analysis suggest that inthe synthetic reaction, the structure of the organic component pyridine and inorganiccomponent polyoxometalate anions in the compounds remain intact. XRDcharacterization shows that compound （1） has amorphousness. Nitrogen adsorptioncharacterization shows good specific surface of the three compounds. Thethermogravimetric analysis shows that the three compounds have good thermal stability.The result of catalytic experiment shows that the three compounds are good at catalyticdegradation of rhodamine B in aqueous solution.（II） Compounds （4）,（5）,（6） are synthesized with macrocyclic copper（CuC₁2H₃0N₆Cl₂O₈） and phosphotungstic acid, phosphomolybdic acid and silicotungstic acid respectively. The element analysis and infrared spectroscopic analysis suggest thatin the synthetic reaction, the structure of the organic component macrocyclic andinorganic component polyoxometalate anions in the compounds remain intact. Thethermogravimetric analysis shows that the three compounds have good thermal stability.The result of catalytic experiment shows that the three compounds are good at catalyticdegradation of rhodamine B in aqueous solution.（III） Compound （7） were synthesized with macrocyclic nickel （NiC₁0H₂6N₆Cl₂O₈）and phosphotungstic acid. The element analysis suggests that in the synthetic reaction,the structure of the organic component macrocyclic and inorganic componentpolyoxometalate anion in the compound remains intact. The result of catalyticexperiment shows that the compound has general effect at catalytic degradation ofrhodamine B in aqueous solution.