Combustion synthesis and luminescence properties of Dy (III) activated NaBaBO 3 phosphor for solid state lighting applications

Abstract

Polycrystalline samples of NaBaBO 3 :Dy 3+ were prepared by employing modified solution combustion synthesis method. The phase formation was confirmed by X-ray powder diffraction (XRD) measurements. The prepared sample was characterized by using SEM and FTIR Techniques. The photoluminescence excitation and emission spectra were measured on HITACHI F-7000 fluorescence spectrometer. Under the excitation of near-UV light, Dy 3+ doped NaBaBO 3 presents the PLE spectra show the excitation peaks from 300 to 400 nm is due to the 4f-4f transitions of Dy 3+ . This mercury-free excitation is useful for solid state lighting and light-emitting diodes. The emission of Dy 3+ ions upon 350 nm excitation is observed at 482 nm due to the 4 F 9/2 → 6 H 15/2 transitions and 574 nm due to 4 F 9/2 → 6 H 13/2 transitions. The CIE chromaticity coordinates for NaBaBO 3 :Dy 3+ phosphors are simulated and located in the bluish-white region. The phosphor shows an excellent thermal stability on temperature quenching effects. The effect of concentration of Dy 3+ ions on the PL intensity has also been investigated. It has been observed that the powder sample exhibits highest PL emission intensity for Dy 3+ concentration of about 0.01 moles. The results were discussed on the relationship between the structure and the luminescence properties.