Luminescent properties of Mn4+ in an oxyfluoride complex with ultra-high thermal stability.

• A novel oxyfluoride phosphor Cs 3 V 2 O 2 F 7 :Mn4+ was obtained via a facile route. • Red emission of the phosphor exhibits an red-shift compared with fluoride samples. • Cs 3 V 2 O 2 F 7 :Mn4+ exhibits excellent PL properties and ultra-high thermal stability. • A white LED with Cs 3 V 2 O 2 F 7 :Mn4+has good photoelectric performances. Thermal stability is an important parameter of phosphors for high-power LEDs. Herein, we have successfully designed and constructed a novel oxyfluoride phosphor Cs 3 V 2 O 2 F 7 :Mn4+ (CVOF:Mn4+) with a hexagonal structure. Due to its weaker crystal-field and intensive covalency for Mn4+, both excitation and emission of Mn4+ in CVOF:0.15Mn4+have an obvious red-shift in contrast to classical fluoride phosphors. Moreover, CVOF:0.15Mn4+has extremely good thermal stability and its integral emission intensity at 140 °C is 1.77 times higher than the initial value, which meets the requirement of high-power LEDs. A white LED assembled with CVOF:0.15Mn4+and Y 3 Al 5 O 12 :Ce3+ (YAG) exhibits good photoelectric performances with the color correlated temperature of 5127 K and the color rendering index of 89, showing that CVOF:0.15Mn4+could be used as a red component for white LEDs. A new oxyfluoride phosphor Cs 3 V 2 O 2 F 7 :Mn4+ exhibits intense red emission and ultra-high thermal stability for white LEDs [Display omitted] [ABSTRACT FROM AUTHOR]