Preparation, spectroscopic properties and enhanced luminescence of Tb3+-doped LuAG phosphors and transparent ceramics by introduction of Sc3+

Tb-doped LuAG(lutetium aluminum garnet) and LuSAG(lutetium scandium-aluminum garnet) precursors were synthesized through a co-precipitation process, using ammonium hydrogen carbonate as precipitator. Single- phase cubic LuAG/Tb and LuSAG/Tb phosphors were obtained after calcination at 1000 and 1200 C, respectively. These powders could be easily sintered into corresponding transparent LuAG/Tb and LuSAG/Tb ceramics in H2 atmosphere at 1850 C. The PL excitation and emission spectra were recorded for both phosphors and ceramics. Emission spectra of all materials were found to be typical for Tb3+, resulting from radiative relaxation of D level. Both the Tb-doped LuSAG phosphors and ceramics show higher efficient luminescence than LuAG , especially the transparent Tb-doped LuSAG ceramic shows about 150% higher luminescence intensity than transparent Tb-doped LuAG ceramic.