Investigation of luminescent properties of red-emitting Ba(Gd,Eu)B₉O₁₆ phosphors and the effect of Ca and Sr on its luminescent properties

Eu³⁺-doped red-emitting BaGdB₉O₁₆ phosphors were synthesized via a sol–gel process and the conventional solid state method. No concentration quenching of Eu³⁺ was observed in this research work. The effect of Ca²⁺ and Sr²⁺ on the luminescence of BaEuB₉O₁₆ (BEB) phosphor was also investigated. The partial replacement of Ba²⁺ by Sr²⁺ could improve the luminescence intensity of BEB phosphor remarkably. The luminescent intensity of sol–gel derived is comparable with the solid state product and it is about 92 % of solid-state product prepared at 950 °C under 395 nm light excitation. The emission intensity of the sol–gel derived phosphor is about 10 times higher than that of Y_1.95Eu_0.05O₂S at 395 nm light excitation. Compared with the molybdate based recently reported red-emitting phosphors, the emission intensity of our obtained novel phosphors synthesized by various methods are much stronger under 395 nm excitation. Due to high emission intensity and good excitation profile, these phosphors can be used as red-emitting phosphor in solid-state lighting to generate white light.