Preparation and luminescent properties of SrS:Ce by addition of sulphur as a co-activator in SrSO <inf>4</inf>:Ce(SO <inf>4</inf>) <inf>2</inf>.4H <inf>2</inf>O by carbothermal reduction

Ce activated SrS has been prepared from SrSO 4:Ce(SO 4) 2.4H 2O by ecologically acceptable carbothermal reduction in the absence of inert gas and hazardous H 2S environment. The mixtures were fired at 900°C to find out the feasibility of the reduction reaction. In order to understand the compensator behavior we tried with sulfur and various fluxes viz., NH 4Cl, NaCl. The materials synthesized were characterized by XRD, photoluminescence emission (PL) and excitation spectroscopy (PLE) and SEM. The characterization results showed the formation of SrS at 900°C with an increase in luminescence intensity after the addition of sulfur as a co-activator. The bright blue-green emission observed at 480nm and 540nm corresponds to energy bands originating from 2T 2g (5d) to 2F 7/2, 2F 5/2(4f) of Ce 3+ transitions. The excitation spectrum shows a fundamental absorption of SrS host crystal lattice in the lower wavelength region at 283 nm and Ce at 430 nm. © 2005 Materials Research Society.