Analysis of luminescence of Eu3+ doped Lu2Ti2O7 powders with Judd-Ofelt theory

Abstract

Eu3+ doped Lu2Ti2O7 particles of 6 to 10 nm in diameter are prepared by Pechini-type polymerized complex route based on polyesterification between citric acid (CA) and ethylene glycol. X-ray diffraction measurements confirmed that Eu3+ doped Lu2Ti2O7 powders crystallized in the face-centered cubic lattice (Fd3m). Emission spectra displayed characteristic 5D0 →7 FJ (J = 0, 1, 2, 3 and 4) spin forbidden f-f electronic transitions of the Eu3+ ions with the most pronounced emission coming from 5D0 →7 F2 and with the emission decays varying between 0.75 and 0.60 ms for samples doped with different concentration of Eu3+. The Judd-Ofelt theory was applied to the experimental data for the quantitative determination of optical parameters such as Ω2, Ω4 Judd-Ofelt parameters, radiative and nonradiative transition rates and emission quantum efficiency. It was observed that, for all the samples, Ω2 >> Ω4. The luminescence quantum yields were calculated by means of the Judd-Ofelt theory and the highest value 60.83 % is obtained for particles doped with concentration of 3 % Eu3+.

Europium-Doped Ceria–Gadolinium Mixed Oxides: PARAFAC Analysis and High-Resolution Emission Spectroscopy under Cryogenic Conditions for Structural Analysis

“…The Ω 2 parameter is sensitive to the local structure and configuration of the host material and can be correlated with the asymmetry and covalence of the lanthanide ion site (short-range effect), and Ω 4 is related to long-range effects . The larger the Ω 2 , the stronger is the covalence. ,, Our results show that the covalence increases with the amount of Gd 3+ ions. The insignificant difference in the Ω 2 and Ω 4 values of the CeO 2‑ y :Eu 3+ sample measured at 337 nm would point toward a centrosymmetric environment around the Eu 3+ ions.…”

“…The Ω 2 parameter is sensitive to the local structure and configuration of the host material and can be correlated with the asymmetry and covalence of the lanthanide ion site (shortrange effect), and Ω 4 is related to long-range effects. 23 The larger the Ω 2 , the stronger is the covalence. 23,42,43 Our results show that the covalence increases with the amount of Gd 3+ ions.…”

“…23 The larger the Ω 2 , the stronger is the covalence. 23,42,43 Our results show that the covalence increases with the amount of Gd 3+ ions. The insignificant difference in the Ω 2 and Ω 4 values of the CeO 2-y :Eu 3+ sample measured at 337 nm would point toward a centrosymmetric environment around the Eu 3+ ions.…”

“…Judd–Ofelt parameters characterize the local structure and bonding in the vicinity of rare-earth ions. , The Judd–Ofelt approach can yield information on the oscillator strengths, radiative lifetimes (τ R ), transition probabilities ( A ), luminescence branching ratios, quantum efficiencies, and estimates of the degree of Eu 3+ ligand covalency using only three parameters. ,− As the theory is complicated and doing calculations by hand is complex, a number of software programs have been developed to facilitate the process. We used the JOES (Judd–Ofelt from Emission Spectra) software by Ćirić et al for the calculation of the Judd–Ofelt parameters in our study.…”

Red-emission analysis, Judd–Ofelt intensity parameters and laser properties of CdMgZnO:xEu3+ nanocrystals: the effects of Eu3+ concentration

“…In order to quantify the influence of the crystal field (in this case, CdMgZnO) on the Eu 3+ ions' spectral characteristics, we applied the JO theory to the emission spectra. The JO theory provides information about materials doped with lanthanide ions, for example, the oscillation strength, radiative lifetime, transition probability, and an estimate of the degree of ligand covalence [58]. Similarly, the JO parameters (Ω 2 , Ω 4 and Ω 6 ) are helpful in understanding the nature of the local environment of lanthanide ions and the covalence of luminophore-ligand (i.e.…”