The ultraviolet (UV) photon-stimulated reactions in oxygen adsorbed on reduced TiO2(110) are studied. For chemisorbed O2, the photochemistry depends on the O2 coverage with 14% to 40% photodesorbing while the rest either dissociates or remains molecularly adsorbed. However, when physisorbed oxygen is also present, ~70% of the chemisorbed oxygen photodesorbs. UV irradiation results in exchange of atoms between the chemisorbed and phyisorbed oxygen. Annealing to 350 K maximizes these exchange reactions. Remarkably, the chemisorbed species is stable under multiple cycles of UV irradiation, and the atoms in the chemisorbed species can be changed from 18O to 16O and then back to 18O via the exchange reactions with physisorbed oxygen. The results show that annealing oxygen on TiO2(110) to ~350 K produces a stable chemical species with interesting chemical properties.

Photochemistry of chemisorbed and physisorbed O<sub>2 </sub>on rutile TiO<sub>2</sub>(110)

243rd National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.

Photochemistry of chemisorbed and physisorbed O2 on rutile TiO2(110)

Photochemistry of chemisorbed and physisorbed O₂on rutile TiO₂(110)