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RESEARCH PRODUCT

A static SIMS study of superficial reactions (O2, (CN)2) on silver

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Abstract The exposure of silver surfaces to oxygen under about 10 −6 mbar at room temperature was studied mainly by secondary ion mass spectrometry (SIMS) used in a static mode. No reactivity of oxygen appeared under these exposure conditions in accordance with previous works. No modifications in the AES spectra, but an unexpected and huge increase in the intensities of secondary ions such as CN − , CNO − , Ag(CN) − 2 , Ag 2 CN + were observed. Different experiments were performed in order to specify the origin of this unexpected reaction in presence of pure oxygen. Moreover, exposures to pure (CN) 2 and to a mixture of cyanogen and oxygen were performed in order to compare the reactivity of silver towards cyanogen when oxygen was present or not. It was shown that the presence of oxygen enhanced the quantity of adsorbed species and modified the adsorption mode of cyanide species on silver. It was also shown that when the temperature increased, these species rearranged on the surface to a polymerized form of cyanogen molecules.