Peculiarities of the effect of perchlorate ions on electrodeposition of cadmium in aqueous-acetonitrile electrolytes

It is shown that, depending on the composition of aqueous-acetonitrile solv ent, either acetonitrile (AN) molecules or perchlorate anions predominantly adsorb on the electrode. The highest surface concentration of AN and the l owest rate of cadmium electroreduction are observed in the mixture with the most "loosened" structure (x(2) similar to 0.4). The "salting-out" action of mixed solvent in the domains of its structure stabilization primarily ma nifests itself in an increase in the adsorption activity of ClO4- anions an d a corresponding promotion of Cd2+ discharge as a result of psi' effect. T he maximum process rate is observed in the domain, where the AN structure i s ordered by monomeric water molecules.