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arXiv · 1205.1569

Origin of the different conductive behavior in pentavalent-ion-doped anatase and rutile TiO$_2$

Kesong Yang·Ying Dai·Baibiao Huang·Yuan Ping Feng
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Abstract

The electronic properties of pentavalent-ion (Nb$^{5+}$, Ta$^{5+}$, and I$^{5+}$) doped anatase and rutile TiO$_2$ are studied using spin-polarized GGA+\emph{U} calculations. Our calculated results indicate that these two phases of TiO$_2$ exhibit different conductive behavior upon doping. For doped anatase TiO$_2$, some up-spin-polarized Ti 3\emph{d} states lie near the conduction band bottom and cross the Fermi level, showing an \emph{n}-type half-metallic character. For doped rutile TiO$_2$, the Fermi level is pinned between two up-spin-polarized Ti 3\emph{d} gap states, showing an insulating character. These results can account well for the experimental different electronic transport properties in Nb (Ta)-doped anatase and rutile TiO$_2$.

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Kesong Yang, Ying Dai, Baibiao Huang, Yuan Ping Feng. 2012-05-08. Origin of the different conductive behavior in pentavalent-ion-doped anatase and rutile TiO$_2$. https://doi.org/10.1088/0022-3727%2F47%2F27%2F275101

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