The electrochemical double layer on Ag in aqueous solutions was examined ex situ with x-ray photoelectron spectroscopy (XPS), UV-photoelectron spectroscopy (UPS) and ion scattering spectroscopy (ISS). The specimen were removed from the electrolyte with hydrophobic surfaces and under potential control. Potential dependent values for the surface concentrations of the adsorbed anions, cations and the surface excess charge, as well as the amount of adsorbed water were determined. Results obtained for the electrochemical double layer on Ag in several alkaline solutions containing anions such as Cl-, ClO4-, and Br- will be reported and compared to acidic solutions. Clean and oxide covered metal surfaces will be considered. The possibility to determine structural information about the arrangement of the adsorbed anios and cations in the electrochemical double layer from systematic XPS binding energy shifts and UPS work function measurements will be discussed.
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