Step and point defect effects on TiO2(100) reactivity

Abstract The influence of steps and point defects on the reactivity of TiO 2 (100) to H 2 O has been examined using photoemission spectroscopy. A vicinal surface was prepared by polishing a sample 2.6 ± 0.1° off the (100) plane towards [001]. Point defects in the form of oxygen vacancies were introduced onto the stepped and planar 1 × 1 stoichiometric (100) surfaces by thermal annealing, a 1 × 3 ordered defect array being formed. The interaction of H 2 O with TiO 2 (100) at 130 K and 293 K is found to be independent of O vacancy and step density. H 2 O adsorbs molecularly at 130 K and dissociates to form OH at 293 K.