Special Features of Localization of Eu3+ Ion in the Matrix of (GdxY1–x)2O3: Eu3+ Solutions During Sol-Gel Synthesis of the Luminophor

Abstract

Sol-gel synthesis of the (Gd_xY_1–x)₂O₃: Eu³⁺ solid solutions (3.5 mol %) allows for the increase in the energy efficiency of emission of the red luminophor. The study of distribution of the luminescence activator Eu³⁺ has revealed that these ions substitute the Gd³⁺ ones in the cationic sublattice of ternary solid solution. The Eu³⁺ ions are predominantly localized in the noncentrosymmetrical position C₂ at x < 0.50 and in centrosymmetrical position C_3i at x > 0.50. The increase in the Eu³⁺ ions concentration in the C_3i position stabilizes the cubic high-temperature structure of the solid solution in comparison with the monoclinic phase. The solid solution with x = 0.75 has been found to be the most efficient luminophor.