Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 43, 2016
Previous Article Next Article

Energetics of native defects in anatase TiO2: a hybrid density functional study

Author affiliations

Abstract

The energetics and electronic structures of native defects in anatase TiO2 are comprehensively studied using hybrid density functional calculations. We demonstrate that oxygen vacancies (VO) and titanium interstitials (Tii) act as shallow donors, and can form at substantial concentrations, giving rise to free electrons with carrier densities from 1011 to 1019 cm−3 under oxygen-rich and oxygen-poor conditions, respectively. The titanium vacancies (VTi), identified as deep acceptors and induced hole carriers, are incapable of fully compensating for the free electrons originating from the donor-type defects at any oxygen chemical potential. Even under extreme oxygen-rich conditions, the Fermi level, which is determined from the charge neutrality condition among charge defects, electron and hole carriers, is located 2.34 eV above the valence band maximum, indicating that p-type conductivity can never be realized under any growth conditions without external doping. This is consistent with common observations of intrinsic n-type conductivity of TiO2. At a typical annealing temperature and under a typical oxygen partial pressure, the carrier concentration is found to be approximately 5 × 1013 cm−3.

Graphical abstract: Energetics of native defects in anatase TiO2: a hybrid density functional study

Back to tab navigation

Supplementary files

Article information


Submitted
22 Aug 2016
Accepted
09 Oct 2016
First published
10 Oct 2016

Phys. Chem. Chem. Phys., 2016,18, 30040-30046
Article type
Paper

Energetics of native defects in anatase TiO2: a hybrid density functional study

A. Boonchun, P. Reunchan and N. Umezawa, Phys. Chem. Chem. Phys., 2016, 18, 30040
DOI: 10.1039/C6CP05798E

Social activity

Search articles by author

Spotlight

Advertisements