title: The importance of bulk Ti3+ defects in the oxygen chemistry on titania surfaces.
abstract: The role of bulk defects in the oxygen chemistry on reduced rutile TiO(2)(110)-(1 × 1) has been studied by means of temperature-programmed desorption spectroscopy and scanning tunneling microscopy measurements. Following O(2) adsorption at 130 K, the amount of O(2) desorbing at ∼410 K initially increased with increasing density of surface oxygen vacancies but decreased after further reduction of the TiO(2)(110) crystal. We explain these results by withdrawal of excess charge (Ti(3+)) from the TiO(2)(110) lattice to oxygen species on the surface and by a reaction of Ti interstitials with O adatoms upon heating. Important consequences for the understanding of the O(2)-TiO(2) interaction are discussed.
authors.affiliation: Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK 8000 Aarhus C, Denmark.
authors.forename: Estephania
authors.initials: E
authors.lastname: Lira
authors.forename: Stefan
authors.initials: S
authors.lastname: Wendt
authors.forename: Peipei
authors.initials: P
authors.lastname: Huo
authors.forename: Jonas Ø
authors.initials: JØ
authors.lastname: Hansen
authors.forename: Regine
authors.initials: R
authors.lastname: Streber
authors.forename: Søren
authors.initials: S
authors.lastname: Porsgaard
authors.forename: Yinying
authors.initials: Y
authors.lastname: Wei
authors.forename: Ralf
authors.initials: R
authors.lastname: Bechstein
authors.forename: Erik
authors.initials: E
authors.lastname: Lægsgaard
authors.forename: Flemming
authors.initials: F
authors.lastname: Besenbacher