The role of inner counterions within PB films during electrochemical processes

The shape of voltammograms of Prussian Blue films (ferric ferrocyanide, PB) deposited on ITO (indium-tin oxide) electrodes in aqueous KCl, CsCl and NH 4Cl solutions has been studied. These results proved a double role of count ercations during these electrochemical processes. Countercations can either be only retained within the zeolitic pores of the PB structure forming par t of their inner solution, or can also form part of the crystalline structu re of PB films by replacing some iron sites. The different electrochemical behaviour of PB films in the three studied solutions (KCl, CsCl and NH4Cl) is analysed from this point of view. (C) 1999 Elsevier Science Ltd. All rig hts reserved.