An analytical expression describing voltammetric behaviors responses at microdisk electrode for various diffusion conditions and degrees of reversibility is reported in this paper. Results of theoretical calculation m...An analytical expression describing voltammetric behaviors responses at microdisk electrode for various diffusion conditions and degrees of reversibility is reported in this paper. Results of theoretical calculation made it possible to use cyclic voltammetry to evaluate heterogeneous rate constants under intermediate diffusion conditions. At relatively low scan rate, the distortion of current-voltage can be reduced due to small iR drops and charging current. The effects of transfer coefficient, alpha, kinetic parameter, lambda(=k(0)r/4D), and switching potential, xi(8), on potential peak separation are discussed in detail. The relationship obtained in this paper between potential peak separation and lambda is in good agreement with that in Ref. 14, whose authors have got their results by using digital simulation technique. After the experiment of Fe(CN)(6)(4-) oxidation, k(0) and alpha were obtained by the theory of this paper. The result agrees with that in Ref. 19.展开更多
FINE particles have attracted much attention in the past few years due to their unique physical and chemical properties. For gas-evaporated fine metallic particles, a thin oxide layer is usually formed on their surfac...FINE particles have attracted much attention in the past few years due to their unique physical and chemical properties. For gas-evaporated fine metallic particles, a thin oxide layer is usually formed on their surface. According to Ruppin’s prediction, a dielectric coating on metallic particles should have a series of surface modes between ω<sub>TO</sub> and ω<sub>LO</sub>, the long-wavelength transverse and longitudinal optical phonon frequencies of the dielectric. The frequency of展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘An analytical expression describing voltammetric behaviors responses at microdisk electrode for various diffusion conditions and degrees of reversibility is reported in this paper. Results of theoretical calculation made it possible to use cyclic voltammetry to evaluate heterogeneous rate constants under intermediate diffusion conditions. At relatively low scan rate, the distortion of current-voltage can be reduced due to small iR drops and charging current. The effects of transfer coefficient, alpha, kinetic parameter, lambda(=k(0)r/4D), and switching potential, xi(8), on potential peak separation are discussed in detail. The relationship obtained in this paper between potential peak separation and lambda is in good agreement with that in Ref. 14, whose authors have got their results by using digital simulation technique. After the experiment of Fe(CN)(6)(4-) oxidation, k(0) and alpha were obtained by the theory of this paper. The result agrees with that in Ref. 19.
文摘FINE particles have attracted much attention in the past few years due to their unique physical and chemical properties. For gas-evaporated fine metallic particles, a thin oxide layer is usually formed on their surface. According to Ruppin’s prediction, a dielectric coating on metallic particles should have a series of surface modes between ω<sub>TO</sub> and ω<sub>LO</sub>, the long-wavelength transverse and longitudinal optical phonon frequencies of the dielectric. The frequency of
