Photoluminescence and efficiency of Ce3+ in SrS powders

The luminescence efficiency of SrS:Ce powders in the doping range from 0.01 to 1.0 at.% was investigated by photoluminescence decay studies. The radiative decay time of Ce3+ is SrS was determined to be 27 ns. The onset of concentration quenching at concentrations higher than about 0.7 at.% has been obtained. The photoluminescence spectrum of Ce3+ exhibits two emission bands as a consequence of the ground state splitting. The Huang-Rhys factor of the 5d-4f transition was estimated to be about 6. The inhomogeneous broadening of the emission band of samples with higher doping level has been investigated by site-selective and time-resolved spectroscopy.