Kinetic and spectroscopic profiles of three pyridine complexes at a silver electrode using surface-enhanced Raman scattering and evolving factor analysis

Abstract This work uses surface-enhanced Raman scattering (SERS) spectroscopy to examine the speciation of pyridine at a rough silver electrode surface during oxidation–reduction cycles. Evolving factor analysis (EFA), a form of self-modeling curve resolution, is used to analyze sequences of SER spectra. The EFA results are interpreted as the resolved spectra and potential-dependent profiles of discrete surface species, and results in information about the potential dependence of species. The profiles of at least two and possibly three species have been resolved. Two previously known species, an N-bound pyridine adduct of Ag + and a π-bound adduct of Ag 0 , have had their spectra deconvoluted and their potential dependence reassessed. Evidence for a third species at positive potentials is presented, its spectrum is deconvoluted, and it is tentatively assigned as an N-bound pyridine complex with Ag 0 .