CHARACTERIZATION OF HETEROGENEOUS KINETIC-PARAMETERS FROM VOLTAMMETRIC DATA BY COMPUTERIZED PATTERN-RECOGNITION

A method for the estimation of heterogeneous kinetic parameters of an electrochemical reaction has been developed. The parameters are extracted from a single stationary electrode polarogram by a comparison of the real polarogram with a reference file of theoretical polarograms. The Fourier transform was used to represent the voltammogram, and the Euclidean distance in 15-dimensional Fourier space was used as the similarity measure. The problems of noisy real data were minimized by using the natural weighting of lower frequency Fourier coefficients. Five chemical systems of known behavior were used to demonstrate the accuracy of this technique. The on-line computer procedure allows rapid (less than 20 s) prediction of three kinetic parameters, ψ, α, and n, from a single voltammogram. In addition, the procedure provides important diagnostics which can be used to evaluate the confidence of the prediction. These diagnostics were demonstrated in the analysis of the Zn(II) data and the severely overlapped doublet data. © 1979, American Chemical Society. All rights reserved.