Synthesis and characterization of spherical ZrO2:Eu3+ phosphors by spray pyrolysis process

Europium doped zirconia (ZrO{sub 2}:Eu{sup 3+}) powder phosphors consisting of spherical, dense and submicrometer size particles were successfully synthesized by a spray drying process followed by a post annealing treatment process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric and differential thermal analysis (TG-DTA), scanning electron microscope (SEM), photoluminescence (PL) spectra as well as lifetimes were utilized to characterize the prepared samples. The results of XRD indicated that the samples began to crystallize at 500 deg. C, and the crystallinity increased with increasing the annealing temperature. The powders with metastable tetragonal symmetry were obtained at relatively low temperature. The effects of annealing temperature, the Eu{sup 3+} concentration as well as the morphology on the PL intensity were investigated in this work.