Co-adsorption of CO and oxygen on W(110) surfaces

Influence of oxygen adsorption on CO chemisorption behavior over W(110) surfaces was studied using valence band spectra and thermal desorption spectroscopy (TDS). In the absence of O, CO formed a tilted and a vertical structure at 120 K on W(110). In the presence of O coadsorbate, in contrast, formation of the tilted structure of CO was suppressed. CO desorption from oxygen-covered W(110) surfaces showed indication of a strong interaction between adsorbates at ∼900 K, which was absent without O.