Preliminary studies on luminescent terbium-doped thin films prepared by the sol - gel process

Abstract

:Tb thin films have been successfully produced from dichloride ethoxide of zirconium, OEt EtOH and by the sol - gel process. These films show luminescent properties when they are excited with UV light (270 nm). The luminescence spectra present typical transitions from the level belonging to the trivalent terbium ion. The processes used for film deposition were dipping and spinning on glass microscope slides. The films obtained exhibit an average visible transmission between 85 and 95%. The surface profiles show that these films are fairly smooth. The results of x-ray diffraction show that the zirconia coatings present a metastable tetragonal phase. It is observed that such films have excellent properties and are therefore of high technological interest.

Luminescence of rare earth-doped Si–ZrO2 co-sputtered films

“…With a wide optical bandgap of 5.22-5.8 eV [3], that reduces the probability of nonradiative decay, and with a low phonon energy (470 cm À1 ), lower than that of SiO 2 (1100 cm À1 ) and of Al 2 O 3 (870 cm À1 ) [4], that reduces the probability of phonon-assisted non-radiative relaxation, the number and probability of radiative transitions in rare earth-doped ZrO 2 increases, which has made such rare earth-doped oxides interesting for photonic applications. Luminescence in Pr 3+ -, Tb 3+ -, Eu 3+ -, Sm 3+ -, Er 3+ -doped ZrO 2 (bulk, powders, nanocrystals or sol-gel) have been investigated [5][6][7][8][9][10]. Er-doped waveguides and LEDs have also been developed [11,12].…”

Cathodoluminescent and Photoluminescent Properties of Al2O3 Powders Doped with Eu

“…Some of the materials used for this kind of applications are rare-earth (RE) activated oxide phosphors such as Y 2 O 3 [1], In 2 O 3 [2], ZrO 2 [3], ZnO [4], Y 3 Al 5 O 12 [5], etc., activated with Eu, Tb, Ce, and other rare earths. These materials have excellent light output and color rendering capabilities.…”

Synthesis and down conversion emission property of $$\hbox {Eu}^{3+}$$ Eu 3 + doped $$\hbox {LaAlO}_{3}, \hbox {CsAlO}_{2}$$ LaAlO 3 , CsAlO 2 and $$\hbox {LiLaO}_{2}$$ LiLaO 2 phosphors

“…However, the emission intensity decreases above 5 mol% of Eu 3+ ions due to concentration quenching, because of non-radiative interaction between ions, the resonant energy transfer becomes stronger. As the concentration is increased, the Eu 3+ ions are packed closer and closer together, which favors the transfer of energy from one europium ion to the next by a resonance process; the energy eventually reaches a trap from which it is dissipated by non-radiative processes rather than by the emission of visible light (Perea et al 1998;Hayakawa et al 1996). In the present investigation, the intensity of 5 D 0 → 7 F 1 transition at 591 nm is comparable to 5 D 0 → 7 F 2 transition at 616 nm.…”