The concentration quenching of photoluminescence in Eu3+-doped La2O3

Abstract

This work explores the influence of dopant concentration on photoluminescent emission and kinetics of Eu 3+ -doped (0.2−10 at.%) nanocrystalline lanthanumoxide powders. The X-ray diffraction analysis confirmed that all samples crystallize in La 2 O 3 hexagonal phase with space group P3m1. Transmission electron microscopy showed particles with non-uniform shape and diverse size distribution with an average particle size of (95 ± 5) nm. The room temperature photoluminescence spectra of all samples contain characteristic Eu 3+ luminescence lines with the most pronounced red 5 D 0 → 7 F 2 emission at about 626 nm. The maximum intensity of red emission is observed for the sample containing 5 at.% of Eu 3+ ions. The emission kinetics was recorded in the temperature range from 10 K to 300 K. The maximum lifetime value of 0.98 ms obtained for the sample with 0.5 at.% Eu 3+ at room temperature increases up to 1.3 ms at 10 K.

Excellent Color Purity and Luminescence Thermometry Performance in Germanate Tellurite Glass Doped with Eu3+ and Tb3+

“…The integral intensity was the highest for the sample doped with 2% Eu2O3 (Figure 2b). Above that concentration, the quenching mechanism caused the intensity to decrease [34]. The Raman, IR and absorption spectra were aimed to investigate whether the doping with Eu 3+ , Tb 3+ or both has an impact on the structural properties of the studied GTS glasses.…”

A New Ultrafine Luminescent La2O3:Eu3+ Aerogel

“…An increase in the luminescent center concentration should be accompanied by an increase in the intensity of emitted light due to higher absorption efficiency [ 33 ]. In Figure 8 , it can be observed that the aerogel with 50% mol of Eu 3+ has the highest luminescence intensity.…”

“…Since the La2O3:Eu 3+ aerogels have a strong emission only at 793 nm, we can assume that the Eu ions might be situated at a symmetrical site. An increase in the luminescent center concentration should be accompanied by an increase in the intensity of emitted light due to higher absorption efficiency [33]. In Figure 8, it can be observed that the aerogel with 50% mol of Eu 3+ has the highest luminescence intensity.…”

“…One way to increase the light intensity of these ions is by inserting them into inorganic compounds (such as La 2 O 3 ), which promotes a transfer of energy to the metal ions and a breaking up of their structural symmetry, leading to an increase in emission intensity [ 29 ]. Also, lanthanum oxide has numerous industrial and technological applications [ 30 , 31 ], including use in luminescent displays and light-emitting diodes (LED) [ 32 ], and La 3+ ions can be easily replaced with luminescence-active Ln 3+ ions over a wide range of concentrations [ 33 ], due to their ionic radius, electronegativity [ 34 ], and electron structure [ 35 ], much like the other lanthanide ions. La 2 O 3 is recognized as an excellent host material for lanthanides in luminescence-related applications [ 36 ], and compared to other lanthanide host matrices, such as Gd 2 O 3 and Lu 2 O 3 , it is cheaper and, therefore, lends itself to more industrial and technological applications [ 37 , 38 ].…”

Síntesis y caracterización de silicatos de itrio codopados con Eu³⁺ y Eu²⁺ con posible aplicación a diodos emisores de luz blanca

“…En dichos estudios, se observa que el fenómeno de desactivación o apagamiento de la emisión, relacionada con la concentración del dopante, generalmente ocurre entre el 3 y el 12%. Sin embargo, los valores registrados con mayor frecuencia oscilan entre el 5 y 7% razón por la cual se eligió el valor promedio, 6% [95][96][97][98][99][100][101][102].…”