Luminescence properties of a new blue-emitting phosphor Ce3+-doped CaLaGa3S7

Abstract A new series of blue-emitting Ce 3+ -doped CaLaGa 3 S 7 thiogallate chalcogenide phosphors were synthesized by a solid-state reaction method. Their luminescence properties were investigated by photoluminescence excitation, emission spectra and lifetime. The critical dopant concentration was found to be 0.15 mol of Ce 3+ ( R c = 15 A) and the fluorescence lifetime of Ce 3+ in CaLaGa 3 S 7 :0.15 Ce 3+ was 12.9 ns. The blue-emitting LED was fabricated by combining an InGaN chip (395 nm) with a CaLaGa 3 S 7 :Ce 3+ phosphor. The CIE chromaticity coordinates of the blue LED were calculated to be (0.14, 0.23).