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 solvent, either acetonitrile (AN) molecules or perchlorate anions predominantly adsorb on the electrode. The highest surface concentration of AN and the lowest rate of cadmium electroreduction are observed in the mixture with the most “loosened” structure (x2 ∼ 0.4). The “salting-out” action of mixed solvent in the domains of its structure stabilization primarily manifests itself in an increase in the adsorption activity of ClO–4 anions and a corresponding promotion of Cd2+ discharge as a result of ψ" effect. The maximum process rate is observed in the domain, where the AN structure is ordered by monomeric water molecules.