VOLTRESISTOMETRY OF NOBLE-METALS AND EXTENSION OF MEASURING CAPABILITY OF THE CONTACT ELECTRORESISTANCE METHOD BY USING IRIDIUM REFERENCE ELECTRODES

The potential dependence of the contact electroresistance (CER) of Ag, Au, Pt and Ir has been investigated in berate buffer solution (pH 9.4 ). The oxidation potentials of these metals were defined and the CER o f its oxides were measured. The CER of Ir at pH 1-14 was shown to have anomalous low values. This made it possible to use Ir as the referenc e specimen (electrode) for measuring high CER values of the oxides of such metals like Ti, Zr and Cr. The CER of oxidized metal surfaces was found to be of non-ohmic nature. A new method has been proposed for a n evaluation in situ of the specific area of defects in oxide films on metals.