Evaluating NaREMgWO₆ (RE = La, Gd, Y) Doubly Ordered Double Perovskites as Eu³⁺ Phosphor Hosts

Abstract

Three doubly ordered double perovskites NaREMgWO (RE = La, Gd, Y) have been synthesized via traditional solid-state methods, doped with Eu, and characterized to evaluate their promise as Eu phosphor hosts. NaYMgWO, a new member of the family, was found to crystallize in the P2 space group and is isostructural with NaGdMgWO. Emissions characteristic of Eu ions (D → F) were observed, with the most intense transition being the D → F transition near 615 nm. Substitution of Eu onto a more compressed RE site in the NaYEuMgWO and NaGdEuMgWO hosts results in a blue shift of the charge-transfer excitation band and an increase in the intensity of the D → F transition compared to NaLaEuMgWO. All of the hosts can incorporate high concentrations of Eu before concentration quenching is observed. When the rare-earth ion is either Gd or Y, good energetic overlap between the Eu charge-transfer band and the absorption of the host lattice results in sensitization and energy transfer from the perovskite host lattice to the Eu activator sites. These hosts display comparable if not better luminescence than YO:Eu, a commonly used commercial standard, demonstrating their promise as red phosphors.

Structure and photoluminescence of Eu3+ doped Sr2InTaO6 red phosphor with high color purity

“…In Table 1 , more detailed crystal structure parameters of the Sr 2 InTaO 6 :0.12Eu 3+ samples are provided and the reliability factors R wp , R p , χ 2 were stable, which illustrate that the refinement results are reliable. 28 From data analysis and comparison, the refinement results confirmed that the crystal belongs to the monoclinic system with a P 121 space group and the cell parameters are calculated to be a = 5.74 Å, b = 5.75 Å, c = 8.12 Å, and α = γ = 90°, β = 89.96°. Moreover, the crystal structure of host Sr 2 InTaO 6 and the around coordination environment of Sr, In and Ta atoms are also shown in Fig.…”

Photoluminescence Properties and Energy Transfers in the Novel LiYMgWO6: Dy3+, Tm3+

“…1c, which matches well with that of monoclinic NaYMgWO 6 with space groups P2 1 in the previous report. 23 However, the peak splitting is much more obvious in the LYMW sample, which may be a result of the reduced symmetry due to the replacement of the relatively larger Na + by the smaller Li + . 24 To obtain the basic electronic properties of the LYMW host, the first-principles calculations are employed in this work.…”

Novel high-efficiency Eu3+-activated Na2Gd2B2O7 red-emitting phosphors with high color purity

“…6(c) that the integrated PL intensity of the Na 2 Gd 2 B 2 O 7 :0.35Eu 3+ phosphor was about 4.7fold higher than that of commercial Y 2 O 2 S:Eu 3+ red phosphor. 60,61 Thermal stability of the Na 2 Gd 2 B 2 O 7 :0.35Eu 3+ sample was examined from room temperature to 210 C upon excitation of 395 nm. The temperature-dependent PL spectra are illustrated in Fig.…”