Verification by surface-enhanced Raman spectroscopy of the integrity of xanthate chemisorbed on silver

Abstract The monolayer chemisorbed from ethyl xanthate solution at the surface of silver has been analysed ex situ by means of Fourier transform-Raman spectroscopy, and the results compared with the corresponding data for multilayer and bulk silver xanthate. The surface layer was deposited on the silver at a controlled potential in the chemisorption region, and the monolayer status of the adsorbate was verified by X-ray photoelectron spectroscopy. The Raman spectra confirmed that xanthate retained its structural integrity in the chemisorbed monolayer, even after the surface had been subjected to ultra high vacuum and soft X-ray irradiation without cooling in the electron spectrometer. Confirmation of the integrity of xanthate chemisorbed on the metallic substrate provides further evidence for the underpotential deposition of thiol collectors on sulphide minerals.