Anatase-to-rutile phase transition of samarium-doped powder detected via the luminescence of

✍ Scribed by Valter Kiisk; Mari Šavel; Valter Reedo; Argo Lukner; Ilmo Sildos

• Book ID: 104078739
• Publisher: Elsevier
• Year: 2009
• Tongue: English
• Weight: 798 KB
• Volume: 2
• Category: Article
• ISSN: 1875-3892
• DOI: 10.1016/j.phpro.2009.07.038

✦ Synopsis

We employed a sol-gel route to prepare 1% samarium-doped TiO 2 nanopowders. Time-resolved photoluminescence (PL) and Raman characterization was performed. After a thermal treatment the powder crystallized in an anatase phase and revealed intense Sm 3+ photoluminescence. The emission spectrum of Sm 3+ exposed well-resolved crystal-field splitting enabling monitoring of the changes in the local environment.

We thoroughly investigated the influence of the annealing treatment (in air) on Sm emission intensity. Annealing up to 800°C led to a systematic enhancement of Sm emission. Annealing at higher temperatures, however, led to a marked weakening of Sm 3+ emission and simultaneous appearance of an emission band near 830 nm. Annealing temperatures as high as 1000°C were needed to induce the phase transition from anatase to rutile. It was possible to use Sm 3+ as a structural probe revealing peculiarities of the phase transition.