Abstract
A series of Dy(3+)/Eu(3+) co-doped Sc(2)(MoO(4))(3) (SMO) phosphors were synthesized via a conventional solid-state reaction. Phase purity and morphology were characterized by X-ray diffraction with Rietveld refinement and scanning electron microscopy, confirming the formation of phase-pure orthorhombic crystals. The electronic structure was investigated through density functional theory calculations combined with diffuse reflectance spectroscopy. Under 266 and 352 nm excitation, the Dy(3+) doped SMO phosphors exhibited characteristic emission peaks at 488 nm ((4)F(9/2) → (6)H(15/2)), 578 nm ((4)F(9/2) → (6)H(13/2)), 667 nm ((4)F(9/2) → (6)H(11/2)), and 761 nm ((4)F(9/2) → (6)H(9/2)). In the Dy(3+)/Eu(3+) co-doped systems, detailed analysis of spectra and luminescence decay kinetics quantitatively confirmed efficient energy transfer from Dy(3+) to Eu(3+). Finally, the optimized SMO:Dy(3+), Eu(3+) phosphors achieved maximum relative (S (r)) and absolute (S (a)) sensitivities of 3.817% K(-1) and 0.018 K(-1), respectively, demonstrating potential for ratiometric optical thermometry applications.