Galvanostatic formation of zinc nuclei on an isotropic pyrolitic carbon electrode from a pure zincate solution and a solution containing an additive of the polymeric tetraalkilammonium salt (TAS) was studied. The process was analyzed taking into account hydrophobic and hydrophilic parts (zones A and B, respectively) of an electrode surface on the charge transfer and crystallization stages. Due to a specific behavior of TAS adsorption on the surface of zones A and B, the nucleation process occurs in two steps. During the first period a few number of nuclei (N~105 cm-2) are formed on sites of zones B which are not occupied by TAS molecules. Under conditions of the constant j and inhibition of nuclei growth it causes an increase of supersaturation and secondary nucleation on occupied by TAS sites of the electrode and formation of a large number of nuclei (N~108 cm-2).

This work is devoted to investigation of the dynamics of charge transfer η D and crystallization η c overpotentials during potentiostatic formation of zinc atoms adsorbed on an isotropic pyrolytic carbon electrode in a zincate solution. We found two reasons for time dependent decrease of η D . The first, the exchange current increases due to gradual activation of the electrode surface by the applied potential pulse. The second reason is increase of the supersaturation. Activation of the electrode is suggested to consist in reduction of oxygen-containing carbon compounds followed by adsorption of water molecules, which participate in the ratecontrolling stage of [Zn(OH) 3 H 2 O] -ion reduction. The time dependent change of the crystallization overpotential as a constituent of the total overpotential η causes redistribution of the η D and η c terms.