THE ELECTROCHEMICAL STUDY OF THE DEPOSITION OF GOLD ONTO COPPER AND ZINC IN AMMONIACAL SOLUTIONS

The deposition of gold onto copper and zinc in ammoniacal solutions ha s been studied using rotating disk electrodes. The cathodic reduction of aurous ammine was studied on a gold rotating disk electrode and the anodic dissolution of copper and zinc was studied in the absence of a urous ammine. The deposition rate is first order with respect to the c oncentration of aurous ammine and is proportional to the square root o f the disk rotating speed. Based on the results obtained, we conclude that the deposition reaction was controlled by mass transfer of aurous ammine to the reaction surface under the experimental conditions.