CHARACTERIZATION OF LUMINESCENT TERBIUM DOPED ZrO₂ FILMS PREPARED BY PNEUMATIC SPRAY PYROLYSIS TECHNIQUE,

M. García, R. Martínez, O. Alvarez-Fregoso, E. Martínez and S. López, Instituto de Investigaciones en Materiales, UNAM, A.P. 70-360 Coyoacan 04510 Mexico, D.F., Mexico.

Terbium doped ZrO₂ photoluminescent films have been prepared by pneumatic spray pyrolysis deposition process. The substrate temperature, the solution flow and the doping concentration in the start solution were varied. It is observed that the crystallinity of the films depends upon the substrate temperature. For substrate temperature lower than 400°C, the deposited films are highly disordered, while for substrate temperature higher than 400°C, the crystalline structure of the prepared material presents the tetragonal metastable phase. The excitation and emission spectra have been obtained. For an excitation wavelength of 250 nm, all the photoluminescent spectra show peaks located at 489 nm, 548 nm, 588 nm and 620 nm. It is observed a concentration quenching of the photoluminescence at values of activator concentration above the 10 atomic percent (a/o), in the spraying solution.