Ms. Cruz et al., NUCLEATION AND GROWTH OF ZINC ELECTRODEPOSITS ON A POLYCRYSTALLINE ZINC ELECTRODE IN THE PRESENCE OF CHLORIDE-IONS, Journal of Applied Electrochemistry, 23(4), 1993, pp. 364-370
The kinetics of the nucleation and growth of zinc on a zinc electrode
in 0.1 m ZnCl2 has been studied by the potential step technique. Four
supporting electrolytes were used: 0.5 m NaCl, 1 M NaCl, 3 M NaCl and
1 m NaClO4. The current decays to a minimum, after which it rises to a
maximum and then decreases again. The initial part of the transient,
up to the current minimum, includes the double layer charging and the
initial nucleation and growth of zinc. The rising part of the transiti
on curve, from the current minimum to the maximum, follows the model o
f progressive nucleation and diffusion-controlled, hemispherical three
dimensional growth. The steady state nucleation rate and the nuclear
number density increase with the overpotential and with the NaCl conce
ntration. The results point to a direct involvement of zinc chlorocomp
lexes in the electrodeposition process.