A novel high thermal stability Ba2CaWO6: Mn4+ far-red emitting phosphor with a double-perovskite structure for plant growth LEDs

A series of Ba2CaW1-xO6: xMn4+ (BCWO: xMn4+) far-red emitting phosphors were successfully synthesized via a high-temperature solid-state reaction method. The phase purity and crystal structure were analyzed by X-ray diffraction (XRD) and Rietveld refinement. The luminescent properties and crystal field strength of Mn4+-occupied octahedra [WO6] environment were estimated according to the photoluminescence (PL) and photoluminescence excitation (PLE) spectra. Under near ultraviolet light (n-UV) excitation, far-red light (peaking at 695 nm) was obtained from BCWO: 0.75%Mn4+, which matches well with the absorption band of the phytochrome PFR. In addition, the thermal stability of the phosphor was investigated according to temperature-dependent PL spectra. The Mn4+ doped Ba2CaWO6 phosphor offers good luminescence performance and high thermal stability, and shows great potential for application in plant cultivation LEDs as a suitable far-red emitting phosphor.