Full-color and thermally stable KSrPO₄:Ln (Ln = Eu, Tb, Sm) phosphors for white-light-emitting diodes

The novel phosphors of KSrPO₄ doped with Eu²⁺, Tb³⁺, and Sm³⁺ were synthesized by solid-state reaction, and their luminescence properties were investigated. The phosphors show pure three-basal-color (red-green-blue) luminescence in the CIE1931 chromaticity diagram, and it was observed that the concentration quenching was dependent on the different dopant contents. This series of phosphate-based phosphors shows higher thermally stable luminescence, which was found to be better than commercially available Y₃Al₅O₁₂:Ce³⁺ phosphor at temperatures higher than 200°C. Considering the situation of high color-rendering index and chemical stability, we have demonstrated that KSrPO₄:Ln (Ln = Eu, Tb, Sm) are potentially useful new scintillation materials for white-light-emitting diodes.