Tunable luminescence of Ce3+/Mn2+-coactivated Sr3Gd(PO4)3 with efficient energy transfer for white-light-emitting diode

► Sr3Gd(PO4)3:Ce3+, Mn2+ phosphors are synthesized by solid state reaction method. ► The spectral overlap between the emission band of Ce3+ and the excitation band of Mn2+ were observed. ► The energy transfer from Ce3+ to Mn2+ in Sr3Gd(PO4)3 host is efficient. ► Sr3Gd(PO4)3:Ce3+, Mn2+ phosphors might be a promising a white-light-emitting phosphor.