STURCTURE AND ELECTRONIC PROPERTIES OF VANADIUM DOPED TiO2

The geometrical structure, electronic structures and band edge positions of rutile TiO2 bulk doped 52.51 ) and with vanadium based on the DFT+U study. The model structures of V(6.25%) and V (12.5%)- doped TiO2 were constructed by using th 48- atom 2 × 2 × 2 super cell of rutile with one and two Ti atom replaced by vanadium respectively. Our calculated results showed that V-V preferred to state in the nearest distance (nn arrangement) in rutile unit cell which explained by the crystalline structure of rutile that provides the stronger metal-metal interaction by lower distance. The band structure results showed V caused two and four localized levels occur in the band gap of rutile by %6.25% and12.5% respectively. An interesting result was shown by altering the direct band gap of pure rutile to the indirect band gap in effect of V-V cluster and also more contraction of band gap in here.

Keywords:

Rutile TiO2 , Band structure , V-doped , DFT+U