Initial stages of copper electrocrystallization from sulfate electrolytes:Cyclic voltammetry on a platinum ring-disk electrode

Initial stages of copper electrocrystallization on platinum rotating and st ationary ring-disk electrodes are studied in sulfate electrolytes of differ ent acidities by cyclic voltammetry with a variable cathodic limit. In a we akly acid sodium sulfate solution of pH 3.7, copper deposition occurs at a higher rate than in a sulfuric acid electrolyte, which is due to an acceler ation of the discharge of copper ions caused by local electrostatic effects that occur during the specific adsorption of sulfate anions and hydroxyl i ons and to alterating nature of electroactive species. The mechanism of the formation of intermediate species lions Cu+) during the deposition and dis solution of copper in solutions of different acidities is established.