Higher-order derivative electronic absorption spectroscopy of ferricyanide electrogenerated in situ by optically transparent thin layer electrochemical cell

Higher-order differential transformations of electronic absorption spectra obtained by in situ thin-layer spectroelectrochemical cell were performed. The characteristics of the derivative spectra obtained in the electrooxidation of ferrocyanide were in good agreement with those of ferricyanide in homogeneous solution systems. Several common crossing points (CCP) appearing in the derivative spectra depending on the applied potential of the reversible system made it clear that the reaction was unitary. The maximum peaks of the derivative spectra corresponding to the shoulders of the original spectra and the applied potential satisfy the Nernstian relationship, which allows us to evaluate the n and Eo0 values in the electrode reaction.