Probing the influence from residual Ti interstitials on water adsorption on TiO2(110)
2012 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 86, no 20, 205415- p.Article in journal (Refereed) Published
Reduced, stoichiometric and oxidized TiO2(110) surfaces have been compared using valence photoelectron spectroscopy. The results show that the intensity from the band-gap state carries contributions from both oxygen surface vacancies and residual Ti interstitials, present after the sample cleaning procedure. The density of Ti interstitials was found to be 0.05 +/- 0.02 monlayers (ML), while the density of oxygen vacancies was estimated to 0.09 +/- 0.01 ML. Both these values are in good agreement with previous STM studies. O 1s core-level photoelectron spectra show that oxidation of the interstitials had negligible effect on the OH-H2O balance within the first water layer. The characteristic OH-H2O balance found on a surface free from oxygen vacancies previously reported [Walle et al., Phys. Rev. B 80, 235436 (2009)] is therefore an inherent property of the TiO2(110) surface; that is, the primary mechanism leading to partial dissociation is not related to the presence of residual Ti interstitials.
Place, publisher, year, edition, pages
2012. Vol. 86, no 20, 205415- p.
IdentifiersURN: urn:nbn:se:uu:diva-187632DOI: 10.1103/PhysRevB.86.205415ISI: 000310868000004OAI: oai:DiVA.org:uu-187632DiVA: diva2:575439