Photoluminescence Properties of Green-Emitting ZnGa2S4:Eu2+ Phosphor

Green-emitting ZnGa2S4:Eu2+ phosphors have been synthesized by solid state reaction. Their luminescence properties have been investigated by photoluminescence excitation and emission spectra, concentration quenching, thermal quenching and photoluminescence decay. The critical dopant concentration is found to be 0.05 mol of Eu2+ and the critical transfer distance of Eu2+ is calculated as 17 angstrom. The thermal quenching result suggests that the phosphor does not have good thermal-quenching property. Its chromaticity coordinates are very close to those of SrGa2S4: Eu2+. Because of their broadband absorption in the region 350-520 nm, the ZnGa2S4: 0.05Eu(2+) phosphor can be a good green phosphor candidate for creating white light in phosphor-converted white LEDs, when combined with RB phosphors and a UV LED. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.099205jes]