Luminescence studies of Eu-doped YBO₃ host

Highly crystalline phase of YBO₃:Eu³⁺ phosphors were prepared by solid state reaction. The phosphor shows characteristic ⁵D₀→⁷F₁ (J = 1, 2, 3, 4) transition for Eu³⁺. Phase purity, and emission intensity increases with increase in the annealing temperature and corresponding Eu-O charge transfer band shows blue shift in excitation spectrum. Color purity, determined in terms of R/O ratio, was found to be 1.42 (CIE color coordinates x = 0.62, y = 0.36). According to the luminescence decay analysis the ⁵D₀ level of Eu³⁺ lifetime is around 5ms and quantum efficiency is 72%. Thermo-luminescence (TL) spectra of the sample reveal three broad peaks between 80 and 240°C.