Dynamic FT-IR. Part I: Rapid-Scan Methods in Spectroelectrochemistry

Abstract

Current rapid-scan FT-IR instrumentation allows medium resolution (16 cm−1) infrared spectra to be acquired and separately stored at a rate of 85 spectra per second with excellent signal-to-noise ratio. This corresponds to a time resolution of about 12 ms. Higher spectral resolutions are possible at a cost of some spectrometer speed. Rapid-scan FT-IR provides a means by which the course of electrochemical reactions can be followed and, unlike digital time-resolved and double-modulation FT-IR, this method is not limited to reversible reactions and may be used with impunity by the nonspecialist. We examine several examples of irreversible electrochemical processes including solution-phase redox chemistry, electropolymerizations, and doping reactions of conducting polymers.