Chemisorption of carbon monoxide and carbon dioxide on gold-supported thorium oxide films

Abstract

The chemisorption of CO and CO/sub 2/ on gold-supported ThO/sub 2/ films has been studied by X-ray photoelectron spectroscopy (XPS). At pressures of approx. 10/sup -5/ Pa both gases were found to adsorb without dissociating at room temperature. The ThO/sub 2/ films were prepared by drying and calcining a Th(NO/sub 3/)/sub 4/-ThO/sub 2/ slurry which was painted onto a gold substrate. Films prepared in this manner were mechanically and chemically stable, and were characterized by Auger electron spectroscopy (AES), X-ray photoelectron spectrosocpy (XPS), X-ray diffraction, and scanning electron microscopy (SEM). The calculated atomic sensitivity factor (ASF) for the Th(4f/sub 7///sub 2/) photoelectron peak (6.7) is in relatively good agreement with the value recently reported in the literature (7.8).