过渡元素杂多钨硅酸盐氧化还原性质的研究

本文通过极谱和循环伏安法,结合紫外光谱和X射线光电子能谱,研究了过渡元素钨硅杂多酸盐KnSiM(H2O)W11O39](M=Mn^2^+,Fe^3^+,Co^2^+,Ni^2^+,Zn^2^+,Cd^2^+)在溶液中的氧化还原性质,提出了它们的还原机理.杂多阴离子的极谱半波还原电位E1/2的顺序为Ni^2^+>Co^2^+>Zn^2^+>Fe^2^+>Mn^2^+,发现杂多阴离子的E1/2与其组分中的过渡元素的电负性X和过渡金属离子与水合电子反应速率常数的对数logke-分别有线性关系,讨论了过渡元素对杂多阴离子氧化还原性的影响.

Studies on the redox properties of heteropolytungstosilicates of transition metals

The redox properties of heteropolytungstosilicates of transition metals KnSiM(H2O)W11O39] (M = Mn2+, Fe3+, Co2+, Ni2+, Zn2+, Cd2+) n solution were studied with polarog. and cyclic voltammetry, together with UV spectroscopy and XPS. The order of the polarog. half-wave potential (E1/2) of heteropoly anions was as follows: Ni2+ > Co2+ > Zn2+ > Fe2+ > Mn2+. The E1/2 values of heteropoly anions were correlated linearly with both the electronegativities of the transition metals, and the logarithm of the rate constants (log k) of the reaction of transition metal ions with hydrated electrons. The reduction mechanism and effects of transition metals on the redox properties of the heteropoly anions are discussed.