Potential Modulation Normal Incidence Reflection Absorption UV-Visible Spectroscopy under Forced Convection: Experimental Aspects

Various aspects of the theory of potential-modulation normal-incidence reflection absorption spectroscopy at a rotating disk electrode have been verified experimentally using the oxidation of iron(II)-hexacyanide ion in aqueous electrolytes as a model system. In particular, excellent quantitative agreement was found between the spectra of [Fe(CN)⁶]^3- (generated electrochemically), as evaluated from the ratio of the amplitude of the ac and the magnitude of the dc components of the optical signal and that obtained by conventional means in a wavelength range in which only the absorption of the product is significant.