Voltammetric Study of the Cathodic Behavior of Copper, Nickel and Zinc Ions in Ammonia Solutions

Abstract

Annotation. The article presents the results of the study of the electrochemical behavior of Cu2+, Ni2+, Zn2+ by voltammetry on stationary solid electrodes. Polarizable working electrodes (copper, titanium) were used for measurements. The value of the half-wave potentials on the titanium electrode shifts to the negative region with an increase in the concentration of ions in the solution, while on the copper one it remains at the same level. The addition of glycine shifts the half-wave potential of both copper and nickel, zinc to the negative region (by 0,07 V for copper, 0,11 V for nickel, 0,12 V for zinc). In the presence of citric acid, the half-wave potential of copper also shifts to a more negative region, while the reduction potentials of copper, nickel and zinc converge, which contributes to their joint electrodeposition.
 Keywords: copper electrolyte, copper, nickel, zinc, voltammetry, electrodeposition.