Synthesis, spectral characteristics and energy transfer of SrLa2Al2O7:Mn4+, Dy3+

Researchers usually co-dope other ions in Mn 4+ doped phosphors to improve and regulate their luminescence properties for the improvement of their practicality. Here, we synthesize SrLa 2 Al 2 O 7 :R (R Dy 3+ , Mn 4+ , and Dy 3+ /Mn 4+ ) samples by solid-state method in air. The crystal structure and phase purity are confirmed by XRD patterns of samples. We investigate the morphology, luminescence properties, optimal doping concentration of Dy 3+ and Mn 4+ ions, lifetimes as well as the energy transfer from Dy 3+ to Mn 4+ ions. We observe yellow emission of SrLa 2 Al 2 O 7 :Dy 3+ under excitation 355 nm in the region from 450 nm to 650 nm with chromaticity coordinates (0.4684, 0.5035) due to the 4 F 9/2  →  6 H 15/2 and 6 H 13/2 transitions of Dy 3+ ion. SrLa 2 Al 2 O 7 :Mn 4+ under excitation 355 nm emits far-red light in the region from 650 nm to 810 nm with chromaticity coordinates (0.7141, 0.2858) due to the transition 2 E g → 4 A 2g of Mn 4+ ion. SrLa 2 Al 2 O 7 :4mol%Dy 3+ , 0.5mol%Mn 4+ under excitation 355 nm contains the emission of both Dy 3+ and Mn 4+ , and shows red emission with chromaticity coordinates (0.5899, 0.4055). The energy transfer process from Dy 3+ to Mn 4+ ions in SrLa 2 Al 2 O 7 :Dy 3+ , Mn 4+ is verified by the spectral characteristics. The luminous mechanisms of samples are analyzed by energy level diagrams of Dy 3+ and Mn 4+ ions.