Luminescence properties and energy transfer investigations of Sr3Lu(PO4)3:Ce3+, Tb3+ phosphors

A series of Ce3+ or Tb3+ doped and Ce3+/Tb3+ co-doped Sr3Lu(PO4)3 phosphors were prepared via the conventional high temperature solid-state reaction. The phase structure, photoluminescence and energy transfer properties of samples were studied in detail. The optimal proportion of Ce3+ single doping is 4 mol% with maximal fluorescence intensity. The Sr3Lu(PO4)3:Ce3+, Tb3+ phosphor shows both a blue emission (428 nm) from Ce3+ and a yellowish-green emission (545 nm) from Tb3+ with considerable intensity under ultraviolet (UV) excitation (268 nm). The energy transfer from Ce3+ to Tb3+ ions takes place in the Sr3Lu(PO4)3:Ce3+, Tb3+ phosphor on the basis of the analysis of the luminescence spectra. The energy transfer mechanism from Ce3+ to Tb3+ ions was proved to be dipole-dipole interaction. The energy transfer behaviors in Sr3Lu(PO4)3:Ce3+, Tb3+ phosphor is also investigated by the lifetime measurement. The results show that this phosphor has potential applications for UV white-light LEDs.