Electrochemical transfer behavior of V ⅤW 11 -V Ⅴ 3W 9 heteropoly anions on the water/nitrobenzene interface was investigated by means of cyclic voltammetry. The effect of the solution acidity on the transfe...Electrochemical transfer behavior of V ⅤW 11 -V Ⅴ 3W 9 heteropoly anions on the water/nitrobenzene interface was investigated by means of cyclic voltammetry. The effect of the solution acidity on the transfer behavior and the stable pH range for the heteropoly anions were studied. The stability of mixed tungstovanadate decreases with increasing the number of vanadium atoms. The main transfer species within the potential window have the negative charges of 4 and the transfer process is diffusion controlled. The apparent transfer potential Δ w o Ψ 0 and the free energy Δ G 0 w→o tr for the heteropoly anions can be obtained from the experimental data. For the different anions, the Δ w o Ψ 1/2 pH relationship can be expressed as: Δ w o Ψ 1/2 =constant-53pH.展开更多
Ten tungstovanadogermanic complexes K 13 H 2[Ln(GeW 10 VO 39 ) 2]· n H 2O (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Yb) were synthesized for the first time. Their structures were characterized by I...Ten tungstovanadogermanic complexes K 13 H 2[Ln(GeW 10 VO 39 ) 2]· n H 2O (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Yb) were synthesized for the first time. Their structures were characterized by IR, UV, ESR, XPS, XRD and magnetic susceptibility. Their redox properties were studied by means of cyclic voctammetry and polargraphy. The results show that the complexes undergo three step reduction, the first step is the double electronic reversible, while the second and the third steps are irreversible. Their thermal stability studied by TG DTA, IR and XRD at various temperature shows that the range of pyrolysis temperature is 450～500 ℃. The complex stability in solution investigated by the acid alkali titration indicates that the range of pH in which the heteropoly anions can exist stably is pH=3 3～7 6 at room temperature.展开更多
Two new compounds of A- type α-and β-K4.5H2.5[SiW9Cr3(OH2)3O37]·xH2O were synthesized. The two kinds of isomers of α-and β-SiW12-xCrx(x=2, 3) were identified by Second-derivative IR spectroscopy and cyclic vo...Two new compounds of A- type α-and β-K4.5H2.5[SiW9Cr3(OH2)3O37]·xH2O were synthesized. The two kinds of isomers of α-and β-SiW12-xCrx(x=2, 3) were identified by Second-derivative IR spectroscopy and cyclic voltammetry. The numbers of electrons involved in reductions were obtained by controlled potential electrolyses of the isomers.展开更多
基金Supported by the NaturalScienceFoundation of China( No.2 0 2 75 0 31) ,the Teaching and Research Award Programfor Outstanding Young Techers in High Education of MOE of China and KJCX- 0 1of Northwest Normal University
文摘Electrochemical transfer behavior of V ⅤW 11 -V Ⅴ 3W 9 heteropoly anions on the water/nitrobenzene interface was investigated by means of cyclic voltammetry. The effect of the solution acidity on the transfer behavior and the stable pH range for the heteropoly anions were studied. The stability of mixed tungstovanadate decreases with increasing the number of vanadium atoms. The main transfer species within the potential window have the negative charges of 4 and the transfer process is diffusion controlled. The apparent transfer potential Δ w o Ψ 0 and the free energy Δ G 0 w→o tr for the heteropoly anions can be obtained from the experimental data. For the different anions, the Δ w o Ψ 1/2 pH relationship can be expressed as: Δ w o Ψ 1/2 =constant-53pH.
文摘Ten tungstovanadogermanic complexes K 13 H 2[Ln(GeW 10 VO 39 ) 2]· n H 2O (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Yb) were synthesized for the first time. Their structures were characterized by IR, UV, ESR, XPS, XRD and magnetic susceptibility. Their redox properties were studied by means of cyclic voctammetry and polargraphy. The results show that the complexes undergo three step reduction, the first step is the double electronic reversible, while the second and the third steps are irreversible. Their thermal stability studied by TG DTA, IR and XRD at various temperature shows that the range of pyrolysis temperature is 450～500 ℃. The complex stability in solution investigated by the acid alkali titration indicates that the range of pH in which the heteropoly anions can exist stably is pH=3 3～7 6 at room temperature.
文摘Two new compounds of A- type α-and β-K4.5H2.5[SiW9Cr3(OH2)3O37]·xH2O were synthesized. The two kinds of isomers of α-and β-SiW12-xCrx(x=2, 3) were identified by Second-derivative IR spectroscopy and cyclic voltammetry. The numbers of electrons involved in reductions were obtained by controlled potential electrolyses of the isomers.
