Combined voltammetry and potentiostatic transient techniques have been
used to study nucleation, formation and growth of thin oxide films on
high purity polycrystalline bismuth in a berate buffer solution, pH =
9.2. It was shown that the initial step in the formation of the conti
nuous anodic layer of bismuth oxide on bismuth is a nucleation process
. The potentiostatic technique was a valuable tool in its study. The o
xide him nucleation kinetics were explained reasonably well through a
3D progressive nucleation and growth mechanism under diffusion control
led growth. Nucleation potential (E-AN), steady-state nucleation rate
(AN(0)) and the number density of growing centre (N-s) are determined.
A detailed mechanistic interpretation of the nucleation process and t
hickening of the anodic layer under potentiodynamic conditions was obt
ained using the criteria of cyclic voltammetry. (C) 1998 Published by
Elsevier Science Ltd. All rights reserved.