Digital Impedance for Faradaic Analysis II. Electrodissolution of Cu in HCI

The electrodissolution of Cu was studied experimentally by both steady-state and impedance (DIFA) techniques on a rotating disk. The anodic dissolution was found to be largely mass-transfer controlled, but a kinetic contribution could be identified at high rotation rates. The steady-state behavior was satisfactorily modeled, and kinetic parameters a_a, a_c and the exchange current density were determined. The impedance of the system was also modeled; experimental results confirmed the steady-state kinetic parameters and the mass-transfer-kinetic model at all frequencies.