Influence of Sr and Mg on Luminescence of CaS Phosphor

Sulfide based phosphors have been studied for more than 100 years. A simple method for preparing calcium sulfide phosphors useful for solid state lighting is described. Ce 3+ and Eu 2+ doped (Ca,Sr)S and (Ca,Mg)S have been synthesized by synthesis of sulfate by re-crystallization method followed by reduction. PL emission of Ce 3+ and Eu 2+ doped (Ca,Sr)S and (Ca, Mg)S phosphor was studied. The effect of different dopant concentration on the PL emission was also investigated. The maximum PL emission intensity was observed when (Ca, Mg)S was doped with 1 mole % of the Ce 3+ . Intense green emission due to d-f transition of Ce 3+ was observed for 450 nm excitation. Intense red emission due to d-f transition of Eu 2+ was observed for 470 nm excitation in (Ca, Mg)S:Eu 2+ . These phosphors will be used for solid state lighting.