Elsevier, Surface Science, 1-3(396), p. 400-410
DOI: 10.1016/s0039-6028(97)00694-8
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Irreversibly adsorbed cyanide adlayers formed on single-crystal platinum electrodes were studied by cyclic voltammetry and in-situ FTIR spectroscopy in a perchloric medium. A vibrational band around 2100 cm−1 was assigned to the C-N stretching vibration of adsorbed cyanide on the three electrode surfaces. Cyanide adlayers seem to be stable on Pt(111) in a wide range of potentials. Tuning rates of 100 and 30 cm−1 V−1 were measured for the band at 2100 cm−1 below and above 0.5 V, respectively. Adsorbed cyanide has a complex behavior on Pt(100). The polarization of the cyanide-covered Pt(100) electrode in the potential region below 0.4 V (RHE) leads to the formation of a CO adlayer (band at 1820 cm−1). The oxidation of adsorbed cyanide on the Pt(100) electrode produces CO2 (band at 2344 cm−1) and adsorbed NO (band at 1624 cm−1), which shows a characteristic voltammetric behavior. Adsorbed cyanate (band at 2175 cm−1) was also identified as an intermediate product during adsorbed cyanide oxidation on Pt(100). Finally, for Pt(110), adsorbed cyanide is slowly desorbed below 0.1 V (RHE). Generalitat Valenciana; DGCYT (PB93/0944)