Luminescent properties of Al2O3:Tb3+ powders embedded in polyethylene terephthalate films

The luminescent properties of Al2O3:Tb3+ powders embedded in polyethylene terephthalate (PET) films have been studied. Luminescent Al2O3:Tb3+ polycrystalline powders were synthesized by a simple evaporation method. The powder embedded films were obtained by the spray pyrolysis technique. The photoluminescence and cathodoluminescence emission spectra from these samples show, in both cases, luminescence peaks associated with transitions within the electronic energy levels of Tb3+ ions. The dominant peak is at 544 nm corresponding to the 5D4 to 7F5 transition. In the case of the powder embedded films, the CIE coordinates depend on the excitation wavelength because there is a blue emission contribution from the PET host. UV-Vis% transmission measurements on these films show that they are transparent (∼80% and 95% T).