Synthesis and luminescence properties of double perovskite Sr2ZnMoO6:Mn4+ deep red phosphor

A double perovskite Sr 2 ZnMoO 6 :Mn 4+ (SZM:Mn 4+ ) phosphor is synthesized by high-temperature solid-state reaction method in air. Emission band peaking at ∼705 nm of SZM:Mn 4+ phosphor in the range of 650–790 nm is attributed to the 2 E → 4 A 2 transition of Mn 4+ ion with activated different lattice vibration modes. Three excitation bands in the range of 210–610 nm are assigned to the O 2− → Mn 4+ charge transfer and the 4 A 2 → ( 4 T 1 , 2 T 2 , and 4 T 2 ) transition of Mn 4+ ion. The optimal Mn 4+ ion concentration is ∼0.8 mol% in SZM:Mn 4+ phosphor. Fluorescence lifetime of SZM:Mn 4+ phosphor decreases from ∼132 μs to 108 μs with increasing Mn 4+ ion concentration in the range of 0.2–1.0 mol%. Time-resolved spectra and fluorescence lifetime data indicate that luminescent center is caused by Mn 4+ ion. The luminous mechanism of SZM:Mn 4+ phosphor is explained by Tanabe-Sugano energy level diagram of Mn 4+ ion. The results are useful to understand the influences of the neighboring coordination environment around Mn 4+ and host crystal structure to the luminescence properties of Mn 4+ ion and develop other novel Mn 4+ -doped materials.