Digital video electrochemistry (DVEC) applied to the study of Prussian Blue films

Abstract

Prussian Blue films were electrogenerated on a Pt disc electrode and color changes were studied by digital video electrochemistry together with cyclic voltammetry. Three systems of peaks were detected. Peaks corresponding to the reduction to the Everitt's Salt form and to the oxidation to Prussian Yellow are well related to color changes expressed as color intensities derivatives. Color changes showed that these peaks involved complexes mechanisms and intermediate species were detected. These also showed the existence of different sites of iron atoms in the crystal structure with different reactivity. A non-zero baseline and a third electrochemical process at the more negative potentials proved not related to color changes.