The energy transfer and effect of doped Mg2+ in Ca3Sc2Si3O12:Ce3+, Pr3+ phosphor for white LEDs

Abstract

The energy transfer and luminescence properties in the Ce³⁺ and Pr³⁺ co-activated Ca₃Sc₂Si₃O₁₂ (CSS) silicate garnet are studied in our work. The addition of Pr³⁺ exhibits a red emission around 610 nm in the green phosphor CSS:Ce³⁺, but the amount of Pr³⁺ incorporated into the phosphor is very limited due to the charge mismatch when Pr³⁺ substitutes for Ca²⁺ in CSS. In order to promote Pr³⁺ incorporation into CSS lattices to enhance the red emission component, the addition of Mg²⁺ incorporated into Sc³⁺ site is performed to compensate the residual positive charge caused by the substitution of Pr³⁺ for Ca²⁺ in CSS. Finally, a white LED with color rendering index of 80 and correlated color temperature of 8715 K is obtained by combining the single CSS:0.05Ce³⁺, 0.01Pr³⁺, 0.3Mg²⁺ phosphor with a blue-emitting InGaN LED chip.