Study On Polyoxomolybdates With Photocatalytic Activity

Polyoxometalates (POMs), as early transition metal oxide clusters, bear many good applications in catalysis, medicine and materials areas. Prominent studies on POM are particularly attractive.In this paper, we use Anderson heteropolymolybtate anion [AIMo6H6O24]3-and Evans-Showell polyoxometalate anion (NH4)6[Co2Mo10O38H4] as building block, by react with transition metal coordinantion and lanthanide cation, We synthesized a series new compounds. These compounds were characterized by elemental analysis, IR, UV, TG, PXRD and single crystal X-ray diffraction. The photocatalytic property of them have also been systematically studied. This dissertation is divided into two parts.1.Three novel3D,2D,1D compounds constructed from polyoxoanions[AlMo6H6O24]3-and3-pyridylacrylic have been synthesized by precisely controlling pH values, when pH=2.50,3D compound1were synthesized, When the pH value was adjusted to3.10compound2with1D chain structure was obtained; When the pH value reached3.50give compound3a2D sheet. When the pyrolysis of crystalline precursors1-3were heated to1000℃, they can lead to the formation of three nanocomposites1’-3’with different forms of silver nanoparticles. Nanocomposites1’-3’not only show good activity in photoatalyzing the degradation of the organic dye RHB under UV conditions but also easy to recycle.2.Four novel compounds4-7constructed from polyoxoanions [Co2Mo10O38H4]6-and lanthanide cations were prepared by solvothermal strategy. The compound4and5are isostructural and they were obtained by lanthanide cations Gd3+/Tb3+link polyoxoanions [Co2Mo10O38H4]6-to form3D microporous structure. The compound6and7that composed by lanthanide cations and polyoxoanions are OD chiral isostructural. Four compounds show good photocatalytic activity for the degradation of the organic dye MO and RHB under visible light.