A double-perovskite Sr2ZnWO6:Mn4+ deep red phosphor: Synthesis and luminescence properties

Novel double-perovskite Sr 2 ZnWO 6 :Mn 4+ (SZW:Mn 4+ ) phosphor is synthesized by high-temperature solid-state reaction method in air. SZW:Mn 4+ phosphor with excitation at 325 and 526   nm emits deep-red light, the chromaticity coordinate is (0.7315,0.2685), and the emission band peaking at ~702   nm within the range 640–760   nm is assigned to the 2 E→ 4 A 2 transition of Mn 4+ ion. The influences of “Mn 4+ - ligand” bonding and crystal field strength to emission properties of Mn 4+ ion are analyzed. The optimal Mn 4+ ion concentration in SZW:Mn 4+ phosphor is ~0.8   mol%. Lifetime of SZW:Mn 4+ phosphor decreases from 554.77 to 401.35   μs with increasing Mn 4+ ion concentration in the range of 0.2–1.0   mol%. The lifetime data and decay curves indicate that there is only a single type of Mn 4+ ion luminescent center in SZW:Mn 4+ phosphor. The luminous mechanism of SZW:Mn 4+ phosphor is analyzed by Tanabe-Sugano energy level diagram of Mn 4+ in the octahedron together with the simple energy level diagram. The experimental results are helpful to research the influences of the neighboring coordination environment around Mn 4+ and host crystal structure to the luminescence properties of Mn 4+ ion and to deeply understand other Mn 4+ -dopedmaterials.