A first principles theoretical study on the diffusion mechanism of Ti interstitials and O vacancies in rutile TiO2 is reported. We find that the diffusion depends strongly on the defect charge. Weakly charged Ti ions diffuse preferentially through the open channels along the c axis with a barrier of ∼0.4 eV. Ti4+ ions, however, diffuse perpendicular to c by an interstitialcy mechanism with a barrier of ∼0.2 eV. Neutral oxygen vacancies diffuse along the c axis with a barrier of 0.65 eV.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films