Complex plane analysis of single pulse data

Abstract

The evaluation of kinetic parameters from galvanostatic and coulostatic step measurements is performed in a new way. The experimental overvoltage/time curve is written as an analytical function and transformed into the Laplace domain. This implicates that the variable time has been replaced by the operational frequency, s, which is given a completely imaginary value, jω. Both the real and imaginary components of the complex electrode impedance can be easily computed for any chosen value of the angular frequency, ω. Subsequent analysis according to the complex plane method delivers the desired information. The procedure is illustrated by application to data obtained with the Cd2+/Cd(Hg) electrode in 1 M Na2SO4 at pH 4.