Optical properties of CaAl(SO4)2Br:RE (RE = Dy, Eu, Ce) novel phosphors.

A new phosphor CaAl(SO4)2Br doped with Dy, Ce and Eu is reported. Rare earth (Dy, Eu and Ce)-doped polycrystalline CaAl(SO4)2Br phosphors were prepared using a wet chemical reaction method and studied for X-ray diffraction and photoluminescence (PL) characteristics. Dy3+ emission in the CaAl(SO4)2Br lattice was observed at 484 and 574 nm in the blue and yellow regions of the spectrum, which are assigned to 4 F9/2→6H15/2 and 4 F9/2→6H13/2 transitions of the Dy3+ ion, respectively. While the PL emission spectra of CaAl(SO4)2Br:Ce phosphor showed Ce3+ emission at 347 nm due to 5d → 4f transition of the Ce3+ ion. In a CaAl(SO4)2Br:Eu lattice, Eu3+ emissions were observed at 593 and 617 nm, coming from the 5D0 → 7 F1 and 5D0 → 7 F2 electron transitions, respectively. The PL study showed that the intensity of electric dipole transition at 617 nm dominates over that of magnetic dipole transition at 590 nm. The maximum PL intensity was obtained for a 1mol% concentration of Eu3+ in CaAl(SO4)2Br host lattice. The results showed that the materialmay be a promising candidate as a blue-, yellow- and red-emitting phosphor.