5D0→7F1 and 5D0→7F2 transition in europium doped halosulphates for mercury-free lamps

Polycrystalline Na3SO4F:Eu and NaMgSO4F:Eu halosulphate phosphors prepared by a wet chemical method have been studied for its photoluminescence (PL) and thermoluminescence (TL) characteristics. Two well resolved peaks are observed at 593 nm and 614 nm, which are assigned to due to 5D0→7F1 and 5D0→7F2 transitions of Eu3+ ions. TL is observed at temperatures between 100 °C and 300 °C. In this paper, we report PL emission spectra of Eu3+ and TL glow curves, which are more sensitive than the standard TLD-CaSO4:Dy. The presented phosphors are applicable for the mercury free lamps and solid state lighting devices.