Enhanced orange-red emission of Sr3La(PO4)3:Ce3+, Mn2+ via energy transfer

A novel orange-red emitting phosphor Sr3La(PO4)3:Ce3+, Mn2+ is synthesized by a high temperature solid state reaction, and its luminescent properties are investigated. The orange-red emission peaked at 605 nm of Mn2+ is greatly enhanced by the sensitizer Ce3+ due to efficient energy transfer from Ce3+ to Mn2+. The energy transfer is demonstrated to belong to a resonant type via a dipole-quadrupole mechanism. The critical distance for Ce3+-Mn2+ energy transfer is calculated to be 1.32 nm by concentration quenching method. The preliminary results indicate that Ce3+ ion may be a optimal sensitizer for the orange-red phosphor Sr3La(PO4)3:Mn2+.