CHARACTERIZATION OF COPPER-OXIDE LAYERS BY ELECTROCHEMICAL METHODS

The applicability of electrochemical methods for the characterization of oxide layers on copper was examined. The oxide layers were formed a t high temperature in air atmosphere and electrochemically in carbonat e and bicarbonate solutions. The test methods were cathodic polarisati on measurements, cyclic voltammograms and galvanostatic reduction. The composition and the thickness of oxide layers were determined from th e galvanostatic curves. The reduction potential range indicates the co mposition of oxide layer and the reduction time indicates the thicknes s of the layer in the galvanostatic E-t curves. The 0,1 M Na2CO3 elect rolyte gave the sharpest reduction peaks in cyclic voltammograms. The cyclic voltammograms also proved that the oxide layers formed in air a t higher temperature differ from the electrochemically formed oxide la yers. Both the parabolic and the logarithmic oxidation rate laws were found to be applicable in air oxidation.