Luminescent characterization of CaAl2S4:Eu powder

The photoluminescent (PL) emission and excitation behaviour of green-emitting CaAl2S4:Eu2+ powder phosphor is reported in detail. CaAl2S4:Eu2+ emission provides good CIE colour coordinates (x=0.141; y=0.721) for the green component in display applications. Powder with a dopant concentration of 8.5 mol% shows the highest luminescence efficiency. Temperature dependence of the radiative properties, such as luminescence intensity and decay time, was investigated. In particular, the Stokes shift, the mean phonon energy, the redshift, the energy of the f→d and d→f transition and the crystal field splitting of the CaAl2S4:Eu2+ emission were determined. The thermal quenching of the emission was examined.