Luminescence Properties of Rare Earth–Doped Cubic Double Perovskite Tungstate Ba_2(1−x)(Na,RE)_xZnWO₆ (RE = Ce³⁺, Eu³⁺ and Dy³⁺) Phosphors

Abstract

Herein, the photoluminescence (PL) and thermoluminescence (TL) properties of rare earth doped cubic double perovskite tungstate Ba2(1−x)(Na,RE)xZnWO6 (RE = Ce3+, Eu3+ and Dy3+) phosphors synthesized by the solid‐state reaction method are presented. The self‐luminescence of pure Ba2ZnWO6 material in the blue‐green region is enhanced by Ce3+ doping with its most effective concentration of 3 mol%. The dominant emission in orange (of Eu3+ at 597 nm) and blue (of Dy3+ at 485 nm) region in the emission spectra of Ba2(1−x)(Na,Eu)xZnWO6 and Ba2(1−x)(Na,Dy)xZnWO6 phosphor, respectively, shows highest intensity for 3 mol% of Eu3+ and 2 mol% of Dy3+ ion in the host lattice. The broad excitation band of Ce3+ and Dy3+ doped phosphor in the near UV region claims its candidature for solid‐state lighting. TL studies are also performed using γ‐radiation. Pure host material shows a simple glow curve while the rare earth ion doped phosphor shows a complex glow curve with enhanced intensity. Phosphor shows the fairly linear response up to 1 kGy radiation. Glow curves are deconvoluted and the trap parameters are calculated by Chen's peak shape method.

Effect of A-Cation Radius on the Structure, Luminescence, and Temperature Sensing of Double Perovskites A2MgWO6 Doped with Dy3+ (A = Ca, Sr, Ba)

“…However, for the Ba compound, there is a clear displacement toward the red region (at 591 nm) because Dy 3+ occupies a high symmetry site ( O h ) with an inversion center, where electric dipole transitions are entirely forbidden according to the SLJ selection rules. Consequently, the spectrum of BMW:2%Dy 3+ ,2%Li + exhibits vibronic lines, similar to the cases of Ba 2 CaWO 6 :Dy, Ba 2 ZnWO 6 :Dy . In these cases, the most prominent emission in the spectrum is the blue emission of the 4 F 9/2 → 6 H 15/2 transition.…”

“…Consequently, the spectrum of BMW:2%Dy 3+ ,2%Li + exhibits vibronic lines, similar to the cases of Ba 2 CaWO 6 :Dy, 23 Ba 2 ZnWO 6 :Dy. 46 In these cases, the most prominent emission in the spectrum is the blue emission of the 4 F 9/2 → 6 H 15/2 transition. Conversely, when Dy 3+ is located in a nonsymmetric site in the lattice, the predominant emission is the yellow emission of the 4 F 9/2 → 6 H 13/2 transition, as reported in various other materials.…”