第四周期过渡金属钼磷三元杂多化合物的氧化还原性质研究

Studies on the Redox Properties of Heteropolymolybdates with Transition Metals

研究了Keggin结构钼磷杂多化合物Na_5[PM(H_2O)Mo_(11)O_(39)]·nH_2O(M=Mn^(2+),Co^(2+),Ni^(2+),Cu^(2+),Zn^(2+)在溶液中的氧化还原性质,发现环境的改变可对杂多阴离子的极谱半波电位产生影响,其影响程度的大小决定于过渡金属离子本身的性质。取代后的钼磷杂多阴离子的半波电位顺序为Ni^(2+)>Co^(2+)>Zn^(2+)>Cu^(2+)>Mn^(2+),pH值的变化影响氧化还原性质,并阐述了变价金属Cu^(2+)对杂多阴离子氧化还原性质的影响.

The redox properties of heteropolymolybdates with transition metals,Na5[PM(H2O) Mo11O39]·nH2O(M=Mn2+,Co2+,Ni2+,Cu2+,Zn2+),in water-dioxane solutions were studied by using electrochemical method.We found the variation of the coordination circumstance would influence the half-wave potential (E1/2) of the heteropoly anions,and the extent of the influence depends on the properties of the inserted transition metals ions.The order of the polaro-graphic half-wave potential of the heteropolyanious substituted by transition metal ions is as follows,Ni2+>Co2+>Zn2+>Cu2+>Mn2+.The effect of Cu2+ ion on the redox properties of the heteropoly anions is discussed in detail.