Off-normal CO2 desorption from the photooxidation of CO on reduced TiO2(110)

Journal Article · Thu Sep 02 04:00:00 EDT 2010 · The Journal of Physical Chemistry Letters, 1(17):2508-2513

DOI:https://doi.org/10.1021/jz100884w· OSTI ID:991073

Petrik, Nikolay G; Kimmel, Gregory A

Photo-induced reactions between O2 and CO on reduced rutile TiO2(110) are studied at low temperature (~30K). Photon stimulated desorption (PSD) of O2, CO2 and CO are observed with comparable yields. Isotope labeling experiments indicate that O2 chemisorbed in a vacancy is more active for photooxidation than O2 chemisorbed on a Ti5c site. The angular distribution for the desorbing CO2 is peaked at ~40º with respect to the surface normal in the azimuth (i.e. perpendicular to the bridging oxygen rows) suggesting that CO2 is produced from O2 occupying an oxygen vacancy and CO adsorbed on a Ti5c site next to it. The experimental results are consistent with CO2 being produced from a transition state complex that has been predicted theoretically. The CO PSD from TiO2(110) is enhanced dramatically by the presence of chemisorbed O2 suggesting that it is a by-product of the CO photooxidation process.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 991073
• Report Number(s): PNNL-SA-73722; KC0301020; KC0302010
• Journal Information: The Journal of Physical Chemistry Letters, 1(17):2508-2513, Journal Name: The Journal of Physical Chemistry Letters, 1(17):2508-2513 Journal Issue: 17 Vol. 1
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CARBON DIOXIDE
CARBON MONOXIDE
CHEMICAL REACTION KINETICS
CHEMISORPTION
DESORPTION
OXIDATION
PHOTOCHEMICAL REACTIONS
TEMPERATURE RANGE 0013-0065 K
TITANIUM OXIDES