A novel red-emitting phosphor, KAl1-xPO4Cl:Eux(3+) (0.1 ≤ x ≤ 1.0)

A series of phosphors KAl1-xPO4Cl:Eux(3+) (0.1 ≤ x ≤ 1.0) was synthesized using a facile combustion method using urea as a fuel and their structural, morphological and photoluminescence properties were investigated. It was found that the particle size was in the range of 1-2 µm with an irregular shape. The f-f transitions of Eu(3+)  in the host lattice were assigned and discussed. The excitation and emission spectra indicated that this phosphor can be efficiently excited by ultraviolet (395 nm), and exhibit reddish orange emission corresponding to the (5)D0 →(7)FJ (J = 0, 1, 2) transitions of Eu(3+). The impact of the Eu(3+) concentration on the relative emission intensity was investigated, and the best doping concentration is 0.5. The present study suggests that the KAl0.5PO4Cl:Eu0.5(3+) phosphor is a strong candidate as a red component for phosphor- converted white light-emitting diodes (LEDs).