Luminescent Properties and Mechanism of Gd_1-x-yAlO₃Eu_x,RE_y

GAP:Eu,Re(Gd_1-x-yAlO₃Eu_x,RE_y, RE=Pr or Ce) powders were prepared by a nitrate--citrate process. It is found that luminescent intensity decreases when GAP:Eu is co-doped with Pr or Ce. The phenomena of spectra prove that there is a resonant energy transfer between Eu and Pr, by the absorption and emission of lower-energy phonon, and also Ce sensitizer decreases the activator energy level from host→Eu. The two factors are considered to be the main reasons for decrease of the luminescent intensity for the co-doped GAP:Eu,Re.