Experimental study of the oxidation-reduction reaction on gold electrodes of the tungsten W(VI)/W(V) couple inside the dodecatungstosilicate anion

In this work we have proposed a qualitative mechanism for the first two steps of the reduction of the dodecatungstic anion on a gold electrode using measurements of faradaic impedance. Two types of supporting electrolyte were chosen—sulphate and perchlorate. The effect of competition with adsorbed SO₄^2? could be observed on the first reduction step. In both steps the charge transfer is related with homogeneous proton transfer reactions.