Influence of Li+ doping on photoluminescence properties of Sr5(PO4)3F: Eu3+

Abstract

In this article, the influence of lithium co-doped on Sr5(PO4)3F:Eu3+ halophosphate based phosphor reported. The Sr5(PO4)3F:Eu3+ and Sr5(PO4)3F:Eu3+, Li+ phosphors were prepared by combustion synthesis route using urea as the fuel. The phosphors were characterized by X-ray diffraction (XRD) and photoluminescence (PL) techniques. The powders were annealed at 900°C and 1200°C and characterized by X-ray diffraction (XRD) which shows that the major crystalline phases from the as prepared or annealed powder samples were identical. The PL results show that the incorporation of Li+ ions into the Sr5 (PO4)3F:Eu3+ lattice could induce a remarkable improvement of the PL intensity in red region at 395 nm excitation wavelength. The highest emission intensity was observed with the compound of Eu3+0.5 mol% and Li+0.5 mol% co-doped Sr5(PO4)3F, whose brightness was increased by a factor of more than 3.0 in comparison with that of the Sr5(PO4)3F:Eu3+. 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 trivalent europium co-doped with lithium may be efficient photoluminescent materials for solid-state lighting phosphors as a red component. © 2010 VBRI press.