Energy transfer and thermal stability of Ce3+, Tb3+ co-doped Ca3Si2O4N2 phosphors for white light-emitting diodes

A series of Ca 3 Si 2 O 4 N 2 :Ce 3+ , Tb 3+ phosphors were synthesized and their phase composition and luminescence properties were investigated. Results showed that an efficient energy transfer occurred between the Ce 3+ and Tb 3+ ions. The thermal stability of the Ce 3+ emission was dramatically enhanced upon Tb 3+ doping. The mechanism was attributed to a shift of the configuration coordinate and an increased energy barrier for thermal quenching, which resulted from the enhanced rigid structure of the host. Finally, a white light emitting diode lamp was fabricated, which exhibited excellent properties. These results indicate that Ca 3 Si 2 O 4 N 2 :Ce 3+ , Tb 3+ can serve as promising blue-green emitting phosphors for w-LEDs.