Synthesis, luminescent properties and crystal stabilization of GdAG:Mn2+/Ce3+ via Y3+ doping for warm w-LED application

Abstract In this paper, the (Gd,Y)AG:Mn2+,Ce3+ phosphors were synthesized by high temperature solid-state reaction method. The lattice stabilization, microstructure and fluorescence properties were systematically investigated via XRD, FE-SEM, PLE/PL spectra and fluorescence decay analysis, respectively. Under the excitation of 461 nm, two emission peaks appear at 585 nm and 740 nm, which can be assigned to the transition 5d→4f of Ce3+ and 4T1→6A1 of Mn2+. The color of (Gd,Y)AG:Mn2+,Ce3+ phosphor can be adjusted from yellow to orange-red by changing the doping concentration of Mn2+, and the quenching mechanism of Mn2+ in (Gd,Y)AG: Mn2+,Ce3+ system is attributed to the electric multipole interactions. With the increase of Mn2+ concentrations, the fluorescence lifetime reduced from 152 ns to 9 ns, and the energy transfer efficiency of Ce3+→Mn2+ can be calculated to increase from 35.32% to 95.89%. The underlying mechanisms were thoroughly investigated and elucidated. Furthermore, the thermal stability of (Gd,Y)AG:Mn2+,Ce3+ phosphor systematically studied. The excellent fluorescence properties and high stability of (Gd,Y)AG:Mn2+,Ce3+ phosphor is expected to be widely used in lighting and display areas.