Title of article :
Electronic structures of relaxed BiOX (X = F, Cl, Br, I) photocatalysts
Author/Authors :
Huang، نويسنده , , Wen Lai and Zhu، نويسنده , , Qingshan، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2008
Pages :
8
From page :
1101
To page :
1108
Abstract :
For photocatalysts BiOX (X = F, Cl, Br, I), the atomic sites have been relaxed and the electronic structures have been calculated via the density functional theory (DFT) with or without the adoption of Bi 5d states. BiOF exhibits a direct band gap while the other three species present the indirect feature. The consideration of Bi 5d states results in apparent expansion of the gaps, which are closer to the experimental results. The transition positions are almost independent of the incorporation of Bi 5d states, and the conduction-band bottom flattens with the increase in X atomic number. Both O 2p and X np (n = 2, 3, 4 and 5 for X = F, Cl, Br and I, respectively) states dominate the valence-bands while Bi 6p states contribute most to the conduction-bands. The density peak of the localized X np states in the valence-band shifts towards the valence-band top with the increasing X atomic number, along with certain changes in the valence and conduction bandwidths. Atomic and bond populations, as well as the spatial distribution of orbital density have also been investigated.
Keywords :
Density functional theory , photocatalyst , Density of states , band structure , Bismuth oxyhalide
Journal title :
Computational Materials Science
Serial Year :
2008
Journal title :
Computational Materials Science
Record number :
1683797
Link To Document :
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