Luminescence Concentration Quenching Mechanism in Gd₂O₃:Eu³⁺.

Abstract

Luminescence concentration quenching in Gd2O3:Eu(3+) nanocrystals results from strong interactions among O(2-) ions and Eu(3+) ions. Because all synthesized Gd2O3:Eu(3+) nanocrystals present the same cubic crystalline phase regardless of Eu(3+) concentration, it is possible to study the optical properties as a function of the dopant concentration. The emission intensities and lifetime curves for Gd2O3:Eu(3+) were analyzed by a simple rate equation model to study the interaction between the O(2-) ions and Eu(3+) ions. The rate equation model considers that such interaction is driven by the following energy transfer processes: the direct energy transfer (O(2-) → Eu(3+)), back-transfer (Eu(3+) → O(2-)), and direct energy migration (Eu(3+) → Eu(3+)). The exact solution of this model agrees with the experimental results, luminescence concentration quenching is reproduced and the corresponding energy transfer rates are reported. Quantitative results suggest that the direct energy transfer and direct energy migration processes are the main responsible for the luminescence concentration quenching, whereas the back-transfer process promotes the Eu(3+) emission.

Photoluminescence behavior of ZrO2: Eu3+ with variable concentration of Eu3+ doped phosphor

“…The ratio between the electron dipole and the magnetic dipole is a measure of the site symmetry at which europium is situated. In addition, we can see other energy transitions of Eu 3þ corresponding to 5 D 0 / 7 F 0 near 585 nm and 5 D 0 / 7 F 3 near 628 nm (Chen et al, 2004;De la Rosa, Diaz-Torres, Salas, & Rodríguez, 2005;Jia et al, 2009;Liu, Hong, & Sun, 2004;Meza et al, 2014;Xu et al, 2008) in all the emission luminescence spectra. The 5 D 0 / 7 F 3 transition which is magnetic dipole transition remains independent from the chemical environment of dopant ions whereas the 5 D 0 / 7 F 2 transition which is electric dipole transition.…”

Photoluminescent properties of ZrO2: Tm3+, Tb3+, Eu3+ powders—A combined experimental and theoretical study

“…As Fig. 7(c) shows, the emission intensity of the Eu 3+ ions increases with increasing concentration of Eu 3+ , reaches a maximum at 4 mol.% RE, and decreases thereafter (owing to the quenching effect) [76]. The critical quenching concentration of Eu 3+ is defined as the concentration at which the emission intensity begins to decrease.…”

Synthesis and characterization of Gd(OH)3 and Gd2O3 nanorods

“…Goldys et al employed the hydrogen flame pyrolysis method to synthesize Gd 2 O 3 nanoparticles with size distribution from 2 nm to 300 nm [24]. Lanthanide ion-doped Gd(OH) 3 and Gd 2 O 3 have also been extensively prepared for applications regarding displays [16,[25][26][27] and fluorescence imaging [1,2,4]. Kim et al reported photoluminescence profile imaging of Eu (III)-doped Gd(OH) 3 and Gd 2 O 3 nanorods [9].…”