Mechanism of the reverse dissolution of zinc in the presence of nickel

Cyclic voltammetry and impedance measurements were used to investigate the influence of an additive, triethyl-benzyl-ammonium chloride, on the kinetics of zinc deposition in acidic sulphate electrolytes containing Niu²⁺ ions able to induce the reverse dissolution of zinc deposits. It is shown that the adsorbed additive inhibits both the nucleation and growth of zinc deposits. By competing with the formation of a nickel-containing surface compound responsible for a stimulation of hydrogen evolution, the additive adsorption also inhibits hydrogen evolution and thereby stabilizes the galvanostatic deposition of zinc.