Corrosion Electrochemical Kinetic Study of Copper in Acidic Solution using Scanning Electrochemical Microscopy

The cathodic hydrogen evolution and anodic dissolution behavior of pure copper in acidic solution were investigated by tip generation/substrate collection mode of scanning electrochemical microscopy. The cupric ion generated by copper anodic dissolution without complexation with Cl was directly monitored and quantitatively analyzed in the potential range between 0.266 V and 0.516 V vs NHE. Based on COMSOL simulation and Tafel linear fitting, the standard rate constants and transfer coefficients of hydrogen evolution reaction, copper oxidation to cupric ion and copper ion are 1.28 x 10(-4) cm/s and 0.29, 5.69 x 10(-4) cm/s and 0.42, 1.31 x 10(-4) cm/s and 0.76, respectively. Moreover, both the proton reduction and oxygen reduction reactions strongly depend on the electrode potential, which should be carefully considered and distinguished for polarization curve analysis of Cu in an acidic solution. (C) The Author(s) 2019. Published by ECS.