Improved photoluminescence of green-emitting phosphor Ca3Sc2Si3O12:Ce3+ for white light emitting diodes

Ca3Sc2Si3O12:Ce3+ phosphors with single-phase were successfully synthesized by a gel-combustion method. Annealing atmosphere greatly affected the luminescent properties of the phosphor. The intensity of absorption band at 450 am was greatly increased with a reducing atmosphere, which was very suitable as a color converter in white LED. The absorption at 243 and 311 nm was gradually enhanced with a stronger reducing atmosphere and a new absorption peak at 362 nm appeared in N-2+H-2 mixing gas. The emission intensity also increased when using reducing atmosphere. Meanwhile, the emission peaks slightly moved to the longer wavelength in reducing atmosphere. A white LED with higher color rending index and lower color temperature was obtained by putting our improved product Ca3Sc2Si3O12:Ce3+ green phosphor and Sr2Si5N8:Eu red phosphor onto a blue LED.