Photoluminescence in TiO2 anatase single crystals

doi:10.1016/0038-1098(93)90427-O

Solid State Communications

Volume 87, Issue 9, September 1993, Pages 847-850

https://doi.org/10.1016/0038-1098(93)90427-O Get rights and content

Abstract

Band gap excitation of pure and Al-doped TiO₂ anatase crystals results in visible broad band luminescence which is interpreted as the emission from the self-trapped excitons localized on TiO₆ octahedra. With temperature increasing from liquid helium temperature to room temperature, the photoluminescence spectra of the undoped crystal shift to higher energies, while the spectra of the crystal doped with Al shift to lower energies. The influence of the Al dopant centers is understood as an extrinsic self-trapping effect. The luminescence in TiO₂ anatase is found to be essentially different from that in TiO₂ rutile because of significant structural differences.

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Photoluminescence in TiO2 anatase single crystals

Abstract

J. Cryst. Growth

Solid State Commun.

J. Solid State Chem.

J. Solid State Chem.

Phys. Rev.

J. Luminesc.

Photoluminescence in TiO₂ anatase single crystals