0000000000791204
AUTHOR
R. Tamarit
Stability of Prussian Blue films on ITO electrodes: effect of different anions
Abstract Transformation of insoluble newly deposited Prussian Blue (PB) into the soluble structure stabilizes the film and allows its total oxidation to Prussian Yellow. The stability of PB films in electrochemical processes in successive potential cycling experiments and under long-term chemical attack by an electrolyte depends not only on the cation that takes part but also on the nature of the anion present. In aqueous media, the sulphate ion clearly destabilizes the crystalline structure whereas the nitrate ion favours stabilization. Initial changes in the voltammograms recorded immediately after the spectroscopic tests have been detected in all media. During the immersion period water …
Electrochemical reduction of the nitrite to ammonium ions in presence of [MoO2(O2CC(S)C6H5)2]2−
Abstract Ammonia is formed during potentiostatic reduction of sodium nitrite solutions on the nafion-complex-coated electrode. When (NH4)2[MoO2(O2CC(S)(C6H5)2)2] is present in NaNO2 solutions a polarographic wave is associated to electrocatalytic reduction of nitrite ion. The wave height varies linearly on the concentration of nitrite ion, allowing a procedure for analysing this ion. This electrochemical behaviour distinguishes the nitrite from the nitrate ions. The Mo(VI), Mo(V), and Mo(IV) are involved in catalytic redox processes determining formation of NH4+ from nitrite ions.