Luminescent and thermometric properties of dual emitting Eu2+/Sm3+ co-doped Sr4La(PO4)3O phosphor based on energy transfer

Abstract Eu2+/Sm3+ co-doped dual-emitting Sr4La(PO4)3O phosphors were synthesized through a convenient high temperature solid state reaction in reductive atmosphere. The structure, luminescence, energy transfer and temperature-dependent luminescence properties of Eu2+/Sm3+ co-doped Sr4La(PO4)3O phosphors were researched and analyzed in detail. The blue emission of Eu2+ and the red emission of Sm3+ can work together as FIR signals. Based on the different response characteristics of these two ion emissions to temperature, Sr4La(PO4)3O:Eu2+/Sm3+ phosphor achieves the relative sensitivity of 0.48384%/K and a wide range of temperature measurements from room temperature to 573 K. The results reveal that the Sr4La(PO4)3O: Eu2+/Sm3+ phosphor has an application prospect in the field of high temperature optical thermometry. The energy transfer mechanism is proved to be the dipole-dipole interaction between Eu2+ and Sm3+ ions.