Density Functional Characterization of the Electronic Structure and Visible‐Light Absorption of Cr‐Doped Anatase TiO2
- 2 September 2009
- journal article
- research article
- Published by Wiley in Chemphyschem
- Vol. 10 (13), 2327-2333
- https://doi.org/10.1002/cphc.200900188
Abstract
To evaluate the electronic and optical properties of Cr-doped anatase TiO2, three possible Cr-doped TiO2 models, including Cr at a Ti site (model I), Cr at a Ti site with an oxygen vacancy compensation (model II), and an interstitial Cr site (model III), are studied by means of first principles density functional theory calculations. In model I, the splitting behavior of the Cr 3d states and the insulating properties are successfully depicted by the GGA+U method, from which it is proposed that Cr at a Ti site should exist as Cr4+ instead of the generally believed Cr3+. As a result, the electron transitions between these impurity states, the conduction band (CB), and the valence band (VB), as well as the d–d transitions between occupied and unoccupied Cr 3d states, provide a reasonable explanation for the experimentally observed major and minor absorption bands. In models II and III, the impurity states and associated optical transition processes—as well as the corresponding electron configurations—are examined.Keywords
This publication has 46 references indexed in Scilit:
- Titanium Dioxide Nanomaterials: Synthesis, Properties, Modifications, and ApplicationsChemical Reviews, 2007
- The role of transition metal impurities and oxygen vacancies in the formation of ferromagnetism in Co-doped TiO2Journal of Physics: Condensed Matter, 2006
- Theoretical study of the structure and optical properties of carbon-doped rutile and anatase titanium oxidesThe Journal of Chemical Physics, 2005
- The structural defects and UV–VIS spectral characterization of TiO2 particles doped in the lattice with Cr3+ cationsMaterials Characterization, 2005
- Visible-Light Photocatalysis in Nitrogen-Doped Titanium OxidesScience, 2001
- Electronic and optical properties of anatasePhysical Review B, 2000
- Electron-energy-loss spectra and the structural stability of nickel oxide: An LSDA+U studyPhysical Review B, 1998
- Efficient iterative schemes forab initiototal-energy calculations using a plane-wave basis setPhysical Review B, 1996
- Urbach tail of anatasePhysical Review B, 1995
- Electroabsorption in Rutile (Ti)Physical Review Letters, 1966