Electrical resistance measurement in electrochemical adsorption experiments of lead and bismuth on thin films of gold. II

In this work the charging curves of electrochemically deposited metallic adatoms at the surface of thin gold films are studied simultaneously with the variation of the electrical resistance of the film as a function of the amount adsorbed. In this paper, the conclusions obtained in part I with (111) vicinal orientation are used. The thin gold films deposited on glass have a (111) preferential orientation of their surfaces. This technique has shown the validity of a model of growth of the adlayer with initial adsorption at steps and allowed the determination of the mean disorientation of the small crystals of the film. It has been shown that the mean width of the terraces present at the surface of these crystals is in the range of 1.4 to 2.6 nm depending on the treatment applied to the glass before the deposition of gold, the lower value corresponding to the glass surfaces more perturbed by the treatment. The larger value which corresponds to the smoother glass surfaces are in good agreement with the surface disorientation determined by X-ray diffraction at glancing angle which is around 4° off the (111) base orientation. Characterizations of film samples prepared under the same conditions using Pb or Bi adatoms are in good agreement.