Controlling Ce~(3+) Emission Color in Silicate Garnet Phosphor

摘要

In this report, we discuss the crystal chemistry and luminescence properties of Ce~(3+) activated Lu_(2-x)Ca_(1+x)Mg_(2-x)Sc_xSi_3O_(12) garnets. We identify that the previously published silicate garnets, Lu_2CaMg_2Si_3O_(12) and Ca_3Sc_2Si_3O_(12) form a full solid solution with Sc~(3+) primarily substituting for Mg~(2+) in octahedral and Ca~(2+) substitution in the dodecahedral sites. Within this solid solution, both the lowest energy Ce~(3+) 4f~1→5d~1 excitation peak and the Ce~(3+) 5d~1→ 4f~1 emission peak blueshifts as x increases with emission maximum for x = 0 at ～605mn and x =2 at ～505nm. The reasons for this blueshift in the luminescence spectra is discussed as well as the thermal quenching of these phosphors as a function of composition.