| Abstract: | Carbon monoxide adsorbed on a smooth platinum electrode in the double-layer region was investigated in 1 M HClO4 solution by using in situ polarization modulation IR reflection spectroscopy and an electrochemical oxidation. From the electrochemical oxidation, the adsorbed CO could be distinguished to be comprised of stable and unstable adsorbed CO's. The unstable adsorbed CO constituted about
of the adsorbed CO, and corresponded to linearly adsorbed CO, but the band intensity of the linearly adsorbed CO was not proportional to the amount of unstable adsorbed CO. The stable adsorbed CO constituted about
; it was one-site adsorbed, and was an IR-inactive species. It is presumed that the IR-inactive species is adsorbed on two Pt atoms with the C-O axis parallel to the electrode surface and one of the Pt atoms bound to two CO molecules. |
