Photoluminescence of Eu3+ activated YAlO3 under UV–VUV excitation

YAlO3 and YAlO3:Eu3+ powder phosphors were prepared by the citric-gel method, and the formation of purified crystalline phases of YAlO3 and YAlO3:Eu3+ was dependent on the pH value of the starting solution. The powders prepared with pH 3 yielded a single phase YAlO3 after calcinations at 1000 °C. The spectroscopic properties in UV–vacuum ultraviolet (VUV) range for the orthorhombic structure phosphors YAlO3:Eu3+ were investigated. The broad band centered at 240 nm was assigned to the charge transfer transition between Eu3+ and the neighboring oxygen anions. The other broad band from 120 nm to 160 nm was attributed to the host absorption, which ensures the efficient absorption of the Xe plasma emission lines. The photoluminescent spectra showed the strongest emission at 614 nm corresponding to the electric dipole 5D0 → 7F2 transition of Eu3+, which resulted in good color purity for display and lamps applications.