Photoluminescence characterization of Dy 3+ and Eu 2+ ion in M 5(PO 4) 3F (M = Ba, Sr, Ca) phosphors

Abstract

Photoluminescence investigation of Eu and Dy activated phosphate based phosphors prepared by combustion synthesis, characterized by XRD (X-ray diffraction) and photoluminescence techniques, has been reported. PL excitation spectrum of M 5(PO 4) 3F:Dy phosphors shows the excitation peaks ranging from 300 to 400 nm due to 4f → 4f transitions of Dy 3+ ions. PL emission spectrum of Dy 3+ ion under 348 nm excitation gives PL emission at 482 nm (blue) due to 4F 9/2 → 6H 15/2 transitions, 574 nm (yellow) emission due to 4F 9/2 → 6H 13/2 transitions and 670 nm (red) due to 4F 9/2 → 6H 11/2 transitions, gives BYR (blue–yellow–red) emissions. The Eu 2+ broad band PL emission spectrum was observed in M 5(PO 4) 3F:Eu phosphor at 440 nm in the blue region of the spectrum due to 5d → 4f transition at 352 nm excitation. The 300–400 nm is Hg-free excitation (Hg excitation is 85% 254 nm wavelength of light and 15% other wavelengths), which is characteristic of solid-state lighting phosphors. Hence PL emission in divalent europium and trivalent dysprosium may be efficient photoluminescent materials for solid-state lighting phosphors.