Luminescence and energy transfer properties of color-tunable Sr₄La(PO₄)₃O: Ce³⁺, Tb³⁺, Mn²⁺ phosphors for WLEDs

Abstract

A series of Sr4La(PO4)3O: Ce3+, Tb3+, Mn2+ phosphors have been synthesized with a high temperature solid-state method. The luminescence properties, thermal stability, and energy transfer from Ce3+ to Tb3+ and Mn2+ in Sr4La(PO4)3O were investigated in detail. Through energy transfer, the weak green emission from Tb3+ and red emission from Mn2+ can be significantly enhanced by the introduction of the sensitizer Ce3+ ions. The emission color can be tuned by changing the ratio of Ce3+/Tb3+ and Ce3+/Mn2+ ions. White light was obtained with chromaticity coordinates of (0.3326, 0.3298) in the Sr4La(PO4)3O: 0.12Ce3+, 0.3Mn2+ sample, indicating that the Sr4La(PO4)3O: Ce3+, Tb3+, Mn2+ phosphors may have potential application in white LEDs.