Luminescence properties of NaLa_0.7(MoO₄)₂:R³⁺(R³⁺=Eu³⁺,Tb³⁺) phosphor and energy transfer

A series of Tb³⁺-activated NaLa(MoO₄)₂ phosphates were synthesized by solid-state reaction at 800 ℃ for 5 h. Comprehensive characterization of these samples included X-ray diffraction characteristics, luminescence spectra, scanning electron microscopy and analysis of luminescence decay curves. The luminescence analysis indicated that the strongest emissions occurred at wavelengths of 544 nm, 591 nm, and 615 nm. The colour of the fluorescence emission can change from red-orange to red and then to yellow-green light depending on the cvaoncentration ratio of Eu³⁺ and Tb³⁺ under different excitations. The CIE chromaticity coordinates demonstrated variability across different color ranges, showcasing the phosphor’s capacity for color tuning. The energy yield was 94% when Eu³⁺ was 0.3 in direct comparison.The versatility in color tuning and high energy efficiency of this bis-molybdate phosphor make it a promising candidate for diverse applications in color display technologies and illumination.