Synthesis and Luminescence of Europium-Containing Compositions Based on Yttrium Oxide and Oxyfluorides

By heating the products isolated from an ethyl acetate medium, luminescent europium-containing compositions based on yttrium oxyfluorides and oxide have been synthesized. The concentration of Eu³⁺ ions in the compositions was from 0.10 to 10 at % of the yttrium content. It has been shown that the (Eu_хY_1–х)_nO_n–1F_{n + 2}, (Eu_хY_1–х)OF, (Eu_хY_1–х)₂O₃, and (Eu_хY_1–х)5O₄F₇ phases are formed during the synthesis. The luminescence of the compositions is related to the ⁵D₀ → ⁷F_j electron transitions of Eu³⁺ ions. It depends on the synthesis conditions, the type of matrix, the position of the Eu³⁺ ions in the crystal lattice, the excitation wavelength, and other factors.