Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5350152 | Applied Surface Science | 2017 | 6 Pages |
Abstract
3d transition metal (TM)-doping into 2Â ÃÂ 2Â ÃÂ 2 supercell of rutile-TiO2 has been studied by ab initio band structure calculations based on self-consistent plane-wave method within the first-principle formalism. As a result of doping, 3d states of dopants hybridize with the O 2p and Ti 3d states to provide impurity energy levels, which either modify the valence (conduction) band and/or appear separately in the bandgap of TiO2. We have found that the intermediate impurity energy level shifts towards the valence band (VB) as the atomic number of dopants increases from V to Zn. Band structure calculations reveal that undoped, Sc, Mn, Fe, Co, Ni, Cu, and Zn-doping show the p-type conductivity, whereas doping of V, and Cr in TiO2 lead to the n-type conductivity. On the other hand, for Sc, Cu, and Zn-doping, the Fermi level penetrates into the VB, causing some of the states to appear below the Fermi level which are completely filled with electrons and in turn show inverse Burstein-Moss (BM) effect. As a matter of fact, we have not found BM effect in any of the 3d TM doping case.
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
Mahesh Saini, Mohit Kumar, Tapobrata Som,