Galvanostatic Growth of Passivating Films Under Transient Conditions. I. Model and Quantitative Analysis for the Zn/ZnO System

• DOI: 10.4152/pea.200301015
• Publication Date: 2009-10-21T04:03:33Z
• Authors: C V D Alkaine; M A C Berton; P C Tulio
• Keywords: Transient (computer programming); Transient analysis; Passivation

On the basis of an ohmic model and a Tafel equation describing relations between current density overpotentials in film at metal/film interface, respectively, it is shown that quantitative analysis galvanostatic transients for growth passivating ultra-thin films on so-called non-noble metals can be obtained.As example, ZnO Zn boric/borate buffer solution considered.In this case, values transfer coefficient exchange reaction interface were found to 1.2 0.11 mA cm -2 , respectively.It was single, first occurred low densities two high ones.The ionic resistivity inside film, during transients, has initial constant value region followed by final increase indicating aging process.For variation evolution point defect concentrations taken into account.For with types behaviors found, depending density.An interpretation these results advanced terms concentrations, mobilities recombination rate defects film.