Boron doping effect on the structural, spectral properties and charge transfer mechanism of orthorhombic tungsten bronze β-SrTa₂O₆:Eu³⁺ phosphor

Abstract

In the study, the effect of boron doping on spectral properties and CTB mechanism was investigated by using Eu3+ doped orthorhombic β-SrTa2O6.

Exploring the effect of boron on the grain morphology change and spectral properties of Eu3+ activated barium tantalate phosphor

“…The CTB peaks over 300 nm are related to the ligand nature of TTB structure due to the ligand environment with highly coordinated A and B tunnels. 33,34 As reported in similar studies, 18,29 the CTB transition intensity increased with increasing intensity of magnetic dipole transition or the formal reduction of Eu 3+ to Eu 2+ is increasing. Fig.…”

“…The parameter Ω 4 is related to the electron density of the surrounding ligands, where an increase in the Ω 4 parameter shows a decreased electron density. 18,42 In Table 2, the Ω 2 parameter decreased from 5.299 to 1.506 × 10 −20 cm 2 , and the Ω 4 parameter decreased from 3.794 and 1.541 × 10 −20 cm 2 , with increasing B 3+ concentration, respectively. The decreasing trend in the Ω 2 parameter showed weak covalent or strong ionic character of the Eu–O bond and high local symmetry of the Eu 3+ sites, while the decrease in Ω 4 parameter indicated an increase in the electron density of the surrounding ligands.…”

“…However, the effect of this transition on the calculation is negligible, which has been reported in some studies. 18,29 The spontaneous transition probability ( A ) is related to its dipole strength which can be expressed as eqn (2):where S ED (electric dipole) and S MD (magnetic dipole) are line strengths (in esu 2 cm 2 ), and h is Planck constant. The electric dipole line strengths ( S ED ) from the JO parameters can be calculated by eqn (3):…”

“…26,27 The photoluminescence of boron co-doped Ba 0.88 Mg 0.93 Al 10 O 16.96 :Eu 3+ phosphor has been studied by Dulda et al 28 where the grain size and crystallinity of phosphor increased as the grain shape changed from rod to hexagonal shape. Moreover, some studies have been performed by İlhan et al on Eu 3+ , B 3+ co-doped SrTa 2 O 6 , 18 and Dy 3+ , B 3+ co-doped CdNb 2 O 6 (ref. 19) phosphors, where it is emphasized that the increased luminescence is closely related to grain morphology.…”

Structural Properties, Photoluminescence, and Judd-Ofelt Parameters of Eu3+- Doped CoNb2O6 Phosphor

“…Therefore, the RE ion-activated phosphors lead to numerous innovations in the development of new generation devices in various fields such as screen-display technology, lighting technology, and optical data communication due to some positive features such as long life, energy saving, improved physical durability, fast switching, small size, environmental friendliness, and high efficiency (1-16). The trivalent europium ion (Eu 3+ ) is known for its strong luminescence in the red spectral region, which exhibits interesting spectral properties, as well as having non-degenerate (J=0) first levels of transitions in both the absorption and luminescence spectrum and has a great advantage over other RE ions (10)(11)(12)(13)(14). The trivalent europium ion has 5 D0 → 7 FJ (J=0, 1, 2, 3, 4, 5, 6) transitions.…”