Red luminescence from La2O3:Eu3+ nanophosphor prepared by Sol-Gel method

Abstract

Pure and Eu³⁺ doped La₂O₃ nanophosphor was synthesized by sol gel process. PL spectra of undoped La₂O₃ samples shows broad emission peaks between 400 and 600 nm and Eu³⁺ doped samples show PL emission peaks at 510, 515, 531, 537, 553, 578, 585, 594, 612 and 624 nm. These peaks are attributed to ⁵D₁ → ⁷F₂, ⁵D₁ → ⁷F₂, ⁵D₀ → ⁷F₀, ⁵D₀ → ⁷F₁,⁵D₀ → ⁷F₂ transitions of Eu^{3 +} ions. The electronic dipole transition corresponding to⁵D₀ → ⁷F₂ (624, 612 nm) is stronger than the magnetic dipole transition of ⁵D₀ → ⁷F₁ (585, 594 nm) of Eu³⁺ ions. Luminescence behavior of Eu³⁺ in La₂O₃ is analyzed by Judd–Ofelt intensity parameters.