Optical Diffraction by Electrodes: Use of Fourier Transforms in Spectroelectrochemistry

Abstract

The information content of an electrochemical experiment can be greatly enhanced by the addition of an optical probe to provide spectral information about material generated at the electrode surface. Methods combining UV-visible spectroscopy with electrochemistry were developed in the 1960’s, mainly by Kuwana^1,2 and Murray³ and have proved very valuable for the characterization and monitoring of electrogenerated species. The technique described in this chapter also involves UV-visible spectroscopy of electrochemical processes, but makes use of the diffraction of light by an electrode. The diffraction pattern is a spatial Fourier transform of the illuminated electrode, and contains information about chromophores generated by an electrode process. Advantages of the diffraction approach to spectroelectrochemistry include high sensitivity, fast time response, and the possibility of describing the spatial distribution of chromophore in solution. After a discussion of the objectives of the diffractive approach, its theory and experimental verification will be described.