Syntheses and Characterization of Transition Metal Doped Molybdovanadophosphoric Heteropoly Compounds

摘要

Generally,heteropoly compounds exhibit a rich acid/base and redox chemistry,which makes them attractive fpr applications to biochemistry,analysis,catalysis,photochemistry and other areas [1-3].When some coordinated metal atoms in the he-terpoly anion are substituted for other metal atoms,the framework of the heteropoly anion is still maintained [4-6].Although its physical and chemical properties are substantially changed,thus,its catalytic function can be enhanced [7-14].Traditional synthesis method of the substituted heteropoly compounds often introduces much impurity into the products.The present paper reports an improved method of synthesizing the substituted heteropoly compounds,using fresh molybdovanadophosphoric heteropoly acid as precursor.In our work a series of pure transition metal substituted molybdovanadophosphoric heteropoly compounds Na_6PMo_(10)VMO_(40)·H2O (M=Zn,Fe,Mn,Co,Ni,Cu) were prepared successfully and characterized by ICP,IR,DTA-TGA and cyclic voltammetry.Their thermal stability,oxidition-reduction behaviour and spectroscopic features were discussed in detail.It can be assumed that they exhibit a good thermal stability,oxidation-reduction behaviour and spectroscopic characteristics,and might be promising catalysts.