Investigation on luminescence of emission-tunable Ca 5 Y 3 Na 2 (PO 4 ) 5 SiO 4 F 2 :Eu 2+ ,Tb 3+ ,Mn 2+ phosphors for white LEDs

Abstract To explore new single-phased white-light-emitting luminescent materials, a series of Eu 2+ -Tb 3+ -Mn 2+ doped Ca 5 Y 3 Na 2 (PO 4 ) 5 SiO 4 F 2 (CYNPS) phosphors were synthesized by solid-state reaction method. Eu 2+ in the CYNPS host shows a light blue emission band covering a broad range from 400 to 800 nm. When the Tb 3+ or Mn 2+ is codoped with Eu 2+ , obvious energy transfer from Eu 2+ to Tb 3+ /Mn 2+ appears, which increases the emission intensity of Tb 3+ /Mn 2+ efficiently. To achieve white emission, the Eu 2+ -Tb 3+ -Mn 2+ ions are tridoped. By adjusting the Mn 2+ concentration, the emitting-light-color can be tuned conveniently. Warm white light was gained in the CYNPS:0.07Eu 2+ ,0.18Tb 3+ ,0.15Mn 2+ phosphor with the chromaticity coordinates and correlated color temperature of (0.396, 0.369) and 3487 K, respectively. The investigation reveals that the present phosphors could have potential application in white LEDs.