Donor defects and small polarons on the TiO2(110) surface
- Author(s)
- P.G. Moses, Anderson Janotti, Cesare Franchini, Georg Kresse, Chris G. Van de Walle
- Abstract
The role of defects in the chemical activity of the rutile TiO2(110) surface remains a rich topic of research, despite the rutile (110) being one of the most studied surfaces of transition-metal oxides. Here, we present results from hybrid functional calculations that reconcile apparently disparate views on the impact of donor defects, such as oxygen vacancies and hydrogen impurities, on the electronic structure of the (110) rutile surface. We find that the bridging oxygen vacancy and adsorbed or substitutional hydrogen are actually shallow donors, which do not induce gap states. The excess electrons from these donor centers tend to localize in the form of small polarons, which are the factual cause of the deep states ∼1 eV below the conduction band, often observed in photoelectron spectroscopy measurements. Our results offer a new framework for understanding the surface electronic structure of TiO2 and related oxides.
- Organisation(s)
- Computational Materials Physics
- External organisation(s)
- University of California, Santa Barbara
- Journal
- Journal of Applied Physics
- Volume
- 119
- No. of pages
- 5
- ISSN
- 0021-8979
- DOI
- https://doi.org/10.1063/1.4948239
- Publication date
- 2016
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103025 Quantum mechanics, 103036 Theoretical physics, 103015 Condensed matter, 103009 Solid state physics
- Keywords
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/donor-defects-and-small-polarons-on-the-tio2110-surface(2ed71ebc-b9cc-4eba-8061-161f8696c2b0).html