Eu³⁺-activated potential red-emitting phosphor for solid-state lighting

The intense red-emitting NaCaY_0.2Eu_0.8(MoO₄)₃ phosphor was prepared by using a sol-gel method for the first time. Thermogravimetric-diferential thermal analysis, X-ray diffraction, field-emission scanning electron microscopy, FT-IR and luminescent measurements were used to characterize the NaCaY_0.2Eu_0.8(MoO₄)₃ particles. The resulting products obtained by using the sol-gel method have a narrower size distribution and a more regular particle shape than those obtained by using the solid- state reaction. The spectra analysis indicated that the obtained phosphor could be excited by UV light of 395 nm and visible light of 466 nm, also emits intense red light with a maximum at about 614 nm. The luminescent intensity of sol-gel derived is comparable with the solid state product and it is about 84% of solid-state product under 395 nm light excitation. Comparative study with YAG:Ce and CaS:Eu²⁺ phosphors, suggested that our synthesized phosphor can be used as an efficient red-emitting phosphor to compensate the red deficiency of YAG:Ce phosphor and also can serve as an alternative phosphor to replace sulfide based phosphors in the solid-state lighting applications.