Microdistribution of Electrolytic Nickel Deposits and Their Surface Topography: Effect of Hydrogen

The role of hydrogen and the near-electrode gas–liquid flows in the formation of the nickel surface microrelief on a smooth copper electrode in a sulfate electrolyte is studied at different values of solution pH, current density, and deposit thickness. Depending on the discharge kinetics of ions being reduced and the mechanism of removal of bubbles from the electrode surface, a nickel-plating electrolyte displays either ideal or poor microthrowing and leveling powers. The development of three- and two-dimensional microwaves discovered on the deposits is closely related to the nature of natural-convective motion of electrolyte and the influence exerted by mass transfer on the electrocrystallization process.