VOLTAMMETRY OF FERROCENE IN LOW ELECTROLYTE-SOLUTIONS

The voltammetry of ferrocene in acetonitrile when the [electrolyte]/[ferrocene] ratio is less than one was investigated to determine the validity of a model presented by Oldham (J. Electroanal. Chem., 250 (1988) 1). The voltammograms were found to agree quite well with Oldham's predictions down to an [electrolyte]/[ferrocene] ratio of 0.1. At smaller ratios the distortions of the voltammograms were observed to be underestimated by Oldham's approach. This deviation is explained by convective mass transport that is influencing the voltammetry under these extreme conditions. Evidence is also presented to demonstrate the importance of other intervening equilibria that can occur when the [electrolyte]/[analyte] ratio is less than one.