Radiative properties of Eu2+ in BaGa2S4

A photoluminescence study of the blue-green emitting BaGa2S4:Eu2+ phosphor is reported. Diffuse reflectance, excitation and emission spectra were examined with the aim to enlarge the fundamental knowledge about the emission of the Eu2+ rare earth ion in this lattice. The thermal dependence of the radiative properties and the influence of the Eu2+ concentration were investigated. The Stokes shift, the crystal field splitting and the activation energy of the thermal quenching were determined. By combining these results with data available in literature, we discussed the radiative properties of the BaAl2S4:Eu2+ blue phosphor in relation with those determined in this study for the isostructural BaGa2S4:Eu2+ phosphor.