Correlation between structure and photoluminescence properties of thin films of TiO2 doped Er3+, obtained by the sol-gel process

Type : Article de conférence
Auteur(s) :  Rabah BENSAHA;, Heider DEHDOUH, Manel BRAHIMI, Fouzia ABBAS, Hanene BENSOUYAD, hichem SEDRATI
Année :  2013
Domaine : Physique
Conférence: Advanced Materials World Congress
Résumé en PDF :  (résumé en pdf)
Fulltext en PDF :  (.pdf)
Mots clés :  TiO2 doped Er3+, sol-gel, photoluminescence properties

Résumé : 

In this work, we are interested to the study of the influence of structure on photoluminescence properties of Er3+ doped TiO2 thin films, dip-coated by the sol-gel method. TiO2 thin films and powders obtained are doped with different rates of Erbium (0.1, 0.5, 1, 3 at %) and have undergone an annealing at 450 ° C. Thin films and powders thus obtained were characterized by different techniques: differential scanning calorimetric (DSC), infrared spectroscopy FTIR, Raman spectroscopy and photoluminescence. (DSC) results show that the Erbium causes a shift of the transformation from amorphous TiO2 to anatase crystalline state to the low temperatures and the latter varies according to the percentage of erbium. While the FTIR shows strong absorption peaks around 438 cm-1 and 612 cm-1 corresponding respectively to the vibration Ti-O-Ti and Ti-O of TiO2. In contrast the Raman spectra show the presence of two phases’ anatase and brookite in the case of un-doped thin films and the disappearance of the brookite in those doped with Erbium and annealed at 450 °C. Finally, the photoluminescence curves show the green and red up-conversion emissions. Green emissions are positioned in the range of 520-570 nm (2H11 / 2, 4S3/2 4I15/2), and then for those of the red they are set in the range 640-690 nm (4F9/2, 4I15/2). We also note that the emission intensity of red and green gradually increased when the erbium rate increases.