Interaction of O2 with reduced rutile TiO2(110) surface

The interaction of O2 with a reduced rutile TiO2(110) surface is investigated using density functional theory calculations. We report new insights on the distribution of bridge-bonded oxygen vacancies (BBOVs), the adsorption geometry, formation energy, reaction barrier, and diffusion pathway of O2 o...

Full description

Saved in:
Bibliographic Details
Published in:Surface science 2013-04, Vol.610, p.33-41
Main Authors: Xu, H., Tong, S.Y.
Format: Article
Language:English
Subjects:
Barriers
Condensed matter: electronic structure, electrical, magnetic, and optical properties
Condensed matter: structure, mechanical and thermal properties
Cross-disciplinary physics: materials science
rheology
Density functional theory calculations
Energy of dissociation
Exact sciences and technology
Mathematical analysis
Oxygen vacancies and adsorption
Physics
Reaction pathways
Rutile
Rutile TiO2 surface
Surface chemistry
Titanium
Titanium dioxide
Vacancies
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The interaction of O2 with a reduced rutile TiO2(110) surface is investigated using density functional theory calculations. We report new insights on the distribution of bridge-bonded oxygen vacancies (BBOVs), the adsorption geometry, formation energy, reaction barrier, and diffusion pathway of O2 on the surface. Our calculations confirm that the BBOVs tend to form single point defects because of repulsion between neighboring BBOVs. Converged DFT results indicate that an O2 landing on a reduced r-TiO2(110) surface will adsorb molecularly at low temperatures in good agreement with experimental observations below 100K. At room temperature, oxygen adsorbs dissociatively, after climbing over an energy barrier. The calculations further show that oxygen in dissociative configuration forms an OO complex on the surface, sitting between in-plane oxygen and Ti atoms. These are intrinsic properties of reduced r-TiO2(110) and we have neglected the effect of bulk Ti-interstitials. Finally, the calculations show that two O2 molecules reacting with a bridge-bonded oxygen vacancy can form an ozone molecule at low temperatures. ► BBOVs tend to form single point defects because of repulsion between BBOVs. ► The dissociative adsorption of O2 are more stable than molecular configuration. ► In dissociative configuration, oxygen adatom forms an OO complex on the surface. ► The oxygen adatom can undergo repeated movements between two neighboring Ti atoms. ► Two O2 molecules reacting with a BBOV can form an ozone molecule on the surface.
ISSN:0039-6028
1879-2758
DOI:10.1016/j.susc.2013.01.003