Eu3+ ion distribution in oxyfluoride glass nanocomposites

EPR characterization of erbium in glasses and glass ceramics

“…An alternative approach is the introduction of paramagnetic probes, for which EPR spectra features are sensitive to local structure variations induced by the primary dopant. This principle has been demonstrated in CaF2-containing oxyfluoride glass ceramics co-doped with Gd 3+ and Eu 3+ [46]. Gd 3+ is an excellent EPR probe, which exhibits a strong signal detectable at room temperature, while the fine structure features of the spectrum are host-sensitive [47].…”

“…5. Room temperature EPR spectra of gadolinium/europium co-doped glass ceramics containing CaF2 nanocrystals [46]. Simulation curve represents the expected curve for cubic CaF2:Gd 3+ centres.…”

Simple Method to Estimate Fractional Numbers of Eu3+ Ions in Different Phases in Highly Luminescent ZrO2–SiO2 Nanocomposites

“…It is well‐known that Eu 3+ ions have a milli‐ and submilli‐second 5 D 0 lifetime. [ 17–22,25 ] In contrast, highly symmetric structures of the Eu 3+ ligand result in a decrease in and an increase in the observed 5 D 0 lifetime according to Equation (1). Since I 0–1 and I 0–2 (: 5 D 0 – 7 F 1 transition energy, : 5 D 0 ‐ 7 F 2 transition energy, : 5 D 0 level population), the asymmetry ratio, Λ, is given by approximately Λ ≅ , and more accurately, Λ ac = ~ , indicating a microscopic asymmetry ratio for a given Eu 3+ site (S), Λ S micro (see the later discussion).…”

“…It is well-known that Eu 3þ ions have a milliand submilli-second 5 D 0 lifetime. [17][18][19][20][21][22]25] In contrast, highly symmetric structures of the Eu 3þ ligand result in a decrease in W 0À2 and an increase in the observed 5 D 0 lifetime according to Equation (1). Since I 0-1 ∝ hν 0À1 W 0À1 N 0 and I 0-2 ∝ hν 0À2 W 0À2 N 0 (hν 0À1 : 5 D 0 -7 F 1 transition energy, hν 0À2 : 5 D 0 -7 F 2 transition energy, N 0 : 5 D 0 level population), the asymmetry ratio, Λ, is given by approximately Λ ≅ W 0À2 =W 0À1 , and more accurately,…”

“…As mentioned earlier, ZrO 2 can accept a large amount of RE ions in the lattice structure to easily form a solid solution. In luminescent material research, several types of nanocomposites have been proposed, such as fluorosilicate, [17,18] SnO 2 -SiO 2 , [19,20] TiO 2 -SiO 2 , [21,22] and others. However, there are very few reports quantifying the number of RE ions that can be "statistically" incorporated into nanocrystals, not embedded into the SiO 2 glassy host, which is very often one of the important requirements for further understanding their PL properties.…”