Corrosion inhibition of copper in near neutral aqueous solutions by gamma-pyrodiphenone

The inhibition effect of gamma-pyrodiphenone (gamma PD) on copper corrosion in near neutral sulphate solutions was investigated. Weight loss and polar ization measurements show a high inhibition efficiency (> 96%) of gamma PD on copper corrosion at extremely low concentrations, gamma PD suppresses ac tive copper dissolution and oxygen reduction. The potentiodynamic cathodic reduction measurements showed an inhibition of oxide formation and stabiliz ation of the Cu2O oxide in the presence of gamma PD. XPS measurements sugge sted that the high inhibition effect of gamma PD on copper corrosion is due to the adsorption of gamma PD molecules, as a first stage, and the formati on of a him with a polymer-like structure by coordination of gamma PD with Cu2O on prolonged exposure.