Synthesis, Structure, and Tunable Luminescence Properties of Novel Ba ₃ NaLa ( PO ₄ ) ₃ F : Eu ²⁺ , Mn ²⁺ Phosphors

Abstract

A series of luminescent emission‐tunable phosphors Ba 3 NaLa ( PO 4 ) 3 F : Eu 2+ , Mn 2+ have been prepared by a high‐temperature solid‐state reaction. The Rietveld refinement analysis confirms that the obtained phosphors possess pure apatite crystalline phase and the sites' occupancy of dopant has been also discussed. Upon the excitation of 355 nm, the emission spectra of Ba 3 NaLa ( PO 4 ) 3 F : Eu 2+ , Mn 2+ consist of two broad bands assigned to 5 d –4 f transition of Eu 2+ and 4 T 1 ( 4 G )– 6 A 1 ( 6 S ) transitions of Mn 2+ , respectively. Energy transfer ( ET ) occurs in Eu 2+ , Mn 2+ codoped Ba 3 NaLa ( PO 4 ) 3 F host. On the basis of the thorough analysis and comparison upon their excitation, emission properties, and the decay behaviors, it is demonstrated that the ET mechanism between Eu 2+ and Mn 2+ is ascribed to the exchange interaction, and the tunable emission color in the novel apatite host can be realized.