Photoluminescence spectroscopy of Eu³⁺-doped LiLu(WO₄)₂ powder material prepared by solid-state reaction

In this article, we prepared europium ions (Eu³⁺) doped lithium lutetium double tungstate material using a classical solid-state reaction. X-ray diffraction (XRD), optical absorption and photoluminescence techniques were used to characterize the samples. XRD analysis and structural refinement measurements revealed that LiLu(WO₄)₂ has a monoclinic structure with a P2/n space group with a formula unit (Z = 2). Additionally, we measured, analysed, and discussed the room-temperature photoluminescence emission and excitation spectra of Eu³⁺-doped LiLu(WO4)2. The emission spectra show the intra-configurational red emission characteristic of Eu³⁺ ions, namely ⁵D₀ → ⁷F_j, J = 0–4. The quenching emission by temperature as well as the ⁵D₀ emission decay curves were measured and discussed. It was found that the quenching of luminescence is obtained for 1.5 at% Eu³⁺ concentration. Judd–Ofelt intensity parameters (Ω₂ = 5.26 × 10⁻²⁰ cm² and Ω₄ = 1.04 × 10⁻²⁰ cm²) and the ‘Commission Internationale de l’Eclairage’ (CIE) chromaticity coordinates were calculated from the emission spectrum of LiLu_1−xEu_x(WO₄)₂ for x = 0.015. The results indicate that Eu³⁺-doped LiLu(WO₄)₂ could be a suitable material for solid-state lighting applications.