On the rate of charge transport in solid metal hexacyanoferrates(III,II)

Solid Berlin green, which was placed in a thin layer between two parallel glassy carbon electrodes, has been studied using chronoamperometry and cyclic voltammetry. No difference was practically found between the values of the charge transport diffusion coefficients (D) under transient and steady-state conditions. For solid species, the calculated D value is large (10(-7)cm(2)s(-1)). A change of the D(1/2)c parameter (c - concentration) under the change of the ratio of the electron donor and acceptor sites was observed. For similar concentration of Fe(CN)(6)(3-) and Fe(CN)(6)(4-) in nickel(II) hexacyanoferrate and iron(III) hexacyanoferrate, the D(1/2)c parameter was similar, what implies a common mechanism of charge transport in these systems.