Electrochemical behaviour of copper in neutral aerated chloride solution. I. Steady state investigation.

The electrochemical behaviour of a Cu rotating disc electrode in neutral aerated NaC1 solution was investigated in the cathodic and anodic ranges and at the corrosion potential. In the cathodic range, where the reduction of oxygen takes place, reduction peaks allow the identification and quantitative evaluation of insoluble corrosion products (CuC1 and Cu20 ). In the anodic range Cu is dissolved, most likely as CuC12. A new mechanism for the anodic dissolution is proposed after comparing our data with previously published mechanisms. Corrosion currents were found to decrease with time and to be a function of the rotation rate of the electrode. Both the mixed kinetics of the anodic partial reaction and diffusion through a porous layer seem to be relevant in controlling Icorr.