The anodic behaviour of zinc in aqueous KOH solution—I. Passivation experiments at very high current densities

Abstract

The anodic behaviour of zinc in aqueous potassium hydroxide has been investigated at very high cds (1–10 A/cm 2). Galvanostatic experiments have been made in aqueous KOH (1–12·8 M) for reaction times 0·1 s–0·2 ms. The relationship between the cd and the passivation time follows a √ t relationship. The forms of the overpotential/time curves indicate changes in the ohmic component of the total polarization. Within the time range investigated no evidence was found for a change in the mode of passivation. The effect of an increase of temperature was to increase the passivation time: the magnitude of the increase was greater than expected from the increase in the diffusion coefficient alone.