ANODIZATION OF COPPER MICROELECTRODES IN A COMPLEXING MEDIUM - DETERMINATION OF STABILITY-CONSTANTS OF PRODUCTS

A model is presented for the anodization of a metal electrode by normal pulse voltammetry in complexing medium, The analysis is based on analytical expressions for current during normal pulse voltammetry at a microelectrode, It is applied to the anodization of a copper microdisk electrode in aqueous chloride solutions. Optimization of the fit of the model to the data yields the overall formation constants of CuCl (K-1) and CuCl2- (beta(2)) as log K-1 = 2.93 (+0.02, -0.05) and log beta(2) = 5.54 (+0.12, -0.17), These values agree with those found in the literature. The advantages of this analysis over traditional approaches which employ an approximation of small current are described.