The infrared spectrum of adsorbed carbon monoxide on a platinum surface in the presence of high pressure gas-phase carbon monoxide

A wedge-filter spectrometer was used in a new experimental technique which permits measurement of < 1% absorbance due to the adsorbed species against a background signal which changes by factors of 2 or 3 over the scanned spectral range, even if up to 0.25 atm gas-phase molecules of the adsorbate are present. The method is illustrated for the adsorption of carbon monoxide on unpurified polycrystalline platinum foil with approx. 100 mm Hg of carbon dioxide present in the cell. A shift of the carbon monoxide absorption maximum with changing cell pressure is discussed. Spectra.