Raman spectroscopy of organic species incorporated into electrodeposited gold layers

Surface micro-Raman spectroscopy is employed for the detection of organic species incorporated in gold layers obtained by electrodeposition from baths containing organic additives. The bulk of thick electrodeposited layers is exposed by metallographic polishing and subsequently analysed spectroelectrochemically. In-situ work in 0.1 M KCl aqueous solution proves the possibility of observing spectral features which can be assigned to additives: specifically, bands related to CN (from KAu(CN)(2)) and benzyldimethylphenylammonium chloride (this quaternary ammonium salt is used as a hydrogen scavenger) are recorded. The intensity of the spectra from incorporated organics is a function of SERS-inducing oxidation-reduction cycles (ORC) and electrode polarisation. Surface restructuring brought about by electrochemical polarisation and release of incorporated material to the surface inhere spectroscopy is being carried out can explain the observed steady state and tone dependent phenomena.