Carbon monoxide adsorption on palladium electrodes modified with silver adatoms

Adsorption of carbon monoxide on palladium deposits and smooth polycrystalline palladium is studied in conditions of preliminary accumulation of various amounts of adsorbed silver (ϑAg) on them. It is discovered that carbon monoxide undergoes adsorption on palladium as it does on platinum, i.e. at the sites free of adsorbed silver, virtually without forcing out preliminarily adsorbed silver. At small and medium values of ϑAg in the region of electrodesorption of a mixed layer on palladium, as opposed to Pt/Pt, only two peaks are observed in an anodic voltammetric curve. The nature of the processes that are responsible for the presence of two peaks pertaining to the oxidation of a mixed adsorption layer is discussed.