82
3 Potential- or Adsorbate-Induced Changes in Surface Stress …
Fig. 3.10 a Cyclic voltammogram and b the versus E curve (after the correction of n s = 1.34
was made) of the (111)-textured Au (111) thin-film electrode measured at a potential scan rate of
20 mV s −1 in 0.1 M NaClO 4 solution containing 3 × 10 −3 M NaI [32]. Modified from [32] with
permission from The Electrochemical Society
sharp anodic current peak observed at −0.215 V (SHE) in the anodic potential scan
is caused by the lifting of the reconstructed Au (111)3 × 22
surface and the
broad reversible current peaks centered at about −0.15 V (SHE) correspond to the
adsorption/desorption of iodine, which are consistent with the features of the cyclic
voltammograms measured in 10
−2 M KI solution [31] and in 0.1 M NaClO 4 solution
containing 5 × 10
−3 M NaI [33].
According to Ocko et al. [31], the
p ×
√
3
-iodine phase on Au (111) surface in
10
−2 M KI solution is stable in the potential region between −0.08 and 0.40 V (SHE).
The shift in equilibrium potential of iodine adsorption due to the concentration of
iodide ions in solution can be corrected by using the Nernst equation. It is deduced
that the
p ×
√
3
-iodine phase on Au (111) surface in 0.1 M NaClO 4 solution
3 Potential- or Adsorbate-Induced Changes in Surface Stress …
Fig. 3.10 a Cyclic voltammogram and b the versus E curve (after the correction of n s = 1.34
was made) of the (111)-textured Au (111) thin-film electrode measured at a potential scan rate of
20 mV s −1 in 0.1 M NaClO 4 solution containing 3 × 10 −3 M NaI [32]. Modified from [32] with
permission from The Electrochemical Society
sharp anodic current peak observed at −0.215 V (SHE) in the anodic potential scan
is caused by the lifting of the reconstructed Au (111)3 × 22
surface and the
broad reversible current peaks centered at about −0.15 V (SHE) correspond to the
adsorption/desorption of iodine, which are consistent with the features of the cyclic
voltammograms measured in 10
−2 M KI solution [31] and in 0.1 M NaClO 4 solution
containing 5 × 10
−3 M NaI [33].
According to Ocko et al. [31], the
p ×
√
3
-iodine phase on Au (111) surface in
10
−2 M KI solution is stable in the potential region between −0.08 and 0.40 V (SHE).
The shift in equilibrium potential of iodine adsorption due to the concentration of
iodide ions in solution can be corrected by using the Nernst equation. It is deduced
that the
p ×
√
3
-iodine phase on Au (111) surface in 0.1 M NaClO 4 solution