Charge transport in Prussian Blue films deposited on ITO electrodes

Charge transport processes that can occur in Prussian Blue films deposited on ITO (indium-tin oxide) electrodes in contact with aqueous solutions have been studied. The concentration in the solution of some ions such as the proton or the potassium influence the films conductivity as well as the degree of hydration of the film. This points to the fact that Prussian Blue films act as ionic conductors when they are immersed in aqueous solutions. Furthermore, the apparent diffusion coefficient calculated from impedance spectra of PB films increases with the temperature which confirms the idea of an ionic conductor. The impedance spectra for the Everitt's Salt films, however, differ from the PB films and is much less sensitive to temperature.