NIR photoluminescence and radioluminescence characteristics of Nd ³⁺ doped BaTa ₂ O ₆ phosphor

Abstract Barium tantalate phosphors activated with different concentrations of Nd ³⁺ ion were synthesized via conventional solid state reaction method. The synthesized ceramic powders were characterized by X–ray diffraction ( XRD ), scanning electron microscopy‐energy dispersive spectroscopy ( SEM ‐ EDS ), laser diode ( LD ) excited near infrared ( NIR ) photoluminescence and X‐ray induced radioluminescence ( RL ) analyses. In XRD results, Nd ³⁺ doped BaTa ₂ O ₆ structure with tetragonal tungsten bronze ( TTB ) symmetry was observed to continue up to 10 mol%. In the examination of ceramic powders by SEM , grain size decreased with the increasing doping concentration. By using laser diode excited NIR photoluminescence of BaTa ₂ O ₆ :Nd ³⁺ phosphor exhibited characteristic emissions at 877, 1080, and 1376 nm wavelengths due to ⁴ F _3/2 → ⁴ I _11/2 , ⁴ F _3/2 → ⁴ I _11/2 , and ⁴ F _3/2 → ⁴ I _11/2 band transitions respectively. Scintillation properties of Nd ³⁺ doped samples from UV to near‐ IR spectral region were carried out by the radioluminescence analysis. NIR and scintillation emissions initially increased by the doping concentration, and then decreased due to concentration quenching effect.