Theoretical study of N-doped TiO2 rutile crystals
Kesong Yang1, Ying Dai, Baibiao Huang
1School of Physics and Microelectronics, State Key Laboratory of Crystal Material, Shandong University, Jinan 250100, P. R. China.
Abstract:
The N-doping effects on the electronic and optical properties of TiO2 rutile crystal have been studied using density functional theory (DFT). The calculations of several possible N-doped structures show that band gaps have little reduction but some N 2p states lie within the band gap in the substitutional N to O structure and interstitial N-doped rutile supercell, which results in the reduction of the photon-transition energy and absorption of visible light. In contrast, substitutional N to Ti doped model has a significant band-gap narrowing. The results maybe clarify confusions in nitrogen-doped TiO2 rutile crystal.
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