Synthesis and luminescence properties of Eu³⁺-doped a novel double perovskite Sr₂YTaO₆ phosphor

A novel Sr₂Y_1−xTaO₆:xEu³⁺ (x = 0.04–0.20) red-emitting phosphor was synthesized by using the conventional solid-state reaction method. The crystal structure, photoluminescence properties, thermal stability and decay lifetimes were investigated in detail. Upon near UV light excitation, this sample exhibited a strong red emission peak centered at 612 nm due to ⁵D₀ → ⁷F₂, which indicated that Eu³⁺ occupies low symmetry sites within the Sr₂YTaO₆ host lattice. The optimized doping concentration of Eu³⁺ ion is about 12 mol%. The excellent thermal stability of Sr₂YTaO₆:Eu³⁺ phosphor was tested according to the temperature dependent emission spectra. In addition, the Sr₂Y_1−xEu_xTaO₆ phosphors exhibited good color coordinate (0.6076, 0.3879) and high color purity about 84.55%. All results indicated that the Sr₂Y_1−xTaO₆:xEu³⁺ phosphors can serve as an efficient red phosphor in the white light emitting diodes.