A novel red emitting phosphor CaSc2O4:Eu2+for the warm white LEDs

A novel red emitting phosphor CaSc2O4:Eu2+ (CSO:Eu2+) was synthesized using a high temperature solid-state method. The crystal structure, luminescent properties, temperature characteristics and quantum efficiency of CSO:Eu2+ were detailed explored. Based on the crystal structure and refinement results of CaSc2O4, it has been confirmed that the Eu2+ ions occupy the Sc atomic site of octahedral hexacoordination configuration. CSO:Eu2+ can exhibit an broad emission with an peak at 656 nm and a full width at half maximum (FWHM) of 78 nm under the 460 nm excitation, and the internal quantum efficiency of CSO:Eu2+ can reach 61.5 %. A white light emitting diodes (LEDs) presented a high color rendering index (CRI) of 96.8 and a correlated color temperature (CCT) of 3959 K, which was fabricated by combining a blue LED chip, the CSO:Eu2+ red phosphor, the commercial Y3(Al, Lu)5O12:Ce3+ yellow phosphor. Importantly, the colors of the goods appear more true and vivid under this white LED device compared to commercial white LEDs.