Automated Analysis of Electrochemical Curent Noise from Potentiostatic Conditioning of Passive Iron in Chloride-Containing Solutions

We have demonstrated the applicability of a recently developed automated methodology for processing of electrochemical current noise through the analysis of current records from potentiostatic conditioning of high purity iron thin films in pH 8.4 borate buffer solutions containing low levels of chloride, at potentials below those required for stable pitting. The analysis precisely identifies all anodic current transients and allows us to distinguish carefully between those within the background noise level and those outliers that are considered to indicate the onset of pitting corrosion. A strong potential dependence was observed for the measured characteristics of both the background current noise and the identified pitting events.