A Rotating Ring-Disc Electrode Study of the Hydrogen Evolution during Zinc Deposition from Zincate Electrolytes

The rotating ring-disc electrode technique offers a simple method for determination of the evolved hydrogen by its detection at the ring during zinc deposition on the disc (steel).

Potentiodynamic investigations have established an increased hydrogen production with shifting of the cathode (disc) potential towards the more negative direction.

The measurements of the ring current versus time at constant disc current show that the hydrogen evolution is intensive mainly in the first 1–2 sec of the zinc deposition. Thereafter it decreases gradually and becomes constant after 3–4 min period from the beginning.

It was found from the cathodic and anodic potentiodynamic curves that the process of hydrogen evolution during zinc deposition was stimulated in the presence of the additives in the electrolyte, particularly by the combinations of basic additives and brighteners.