Journal of Electroanalytical Chemistry, Vol.448, No.2, 237-244, 1998
An in situ infrared spectroscopic study of imidazole films on copper electrodes
Organic films electrodeposited on a copper electrode from basic solutions containing imidazole were investigated by two different in situ infrared spectroscopic techniques : real-time polarization modulation and static linear polarization reflection absorption spectroscopy. The spectra indicate that as the electrode potential is made more positive, the amount of imidazole bound to the electrode surface increases. The coating on the electrode is found to consist mainly of copper(I) imidazolate with either a random or perpendicular orientation to the polycrystalline surface. No change in orientation of the imidazole ring is seen with the variation in potential. The infrared data from both reflection techniques indicates that before the Cu(0)/Cu(I) onset the film is formed at the solution metal oxide/hydroxide interface and at potentials above this, greater than or equal to 2 -0.54 V, a more compact film forms closer to the metal surface.
Keywords:TIME POLARIZATION MODULATION;ENHANCED RAMAN-SCATTERING;THIN-FILMS;SURFACES;SILVER;BENZIMIDAZOLE;BENZOTRIAZOLE;ORIENTATION;SERS