Synthesis, luminescence property, and application of a novel red-emitting BaLaZnTaO6:Mn4+ phosphor

A novel red-emitting BaLaZnTaO6:Mn4+ phosphor is synthesized by a solid-state reaction. The phosphor can be excited at 350 nm, which matches well with the near-ultraviolet (UV) InGaN chip (365 nm) for white light-emitting diodes (w-LEDs). UV-visible spectral analysis indicates that doping with Mn4+ ions results in broad absorption bands, which allow the sample to adapt to a wide range of excitation wavelength. A bright red emission peak is found in the photoluminescence spectrum and is attributed to the spin-forbidden (2)Eg -> (4)A(2) transition of Mn4+ ions. All decay times are in the range of microseconds, indicating a forbidden character of infra d-shell transitions in Mn4+. The values of the crystal-field parameters Dq, B, and C are determined as 1980, 660, and 3138 cm(-1), respectively. The quantum efficiency of BLZT:0.0025Mn(4+) phosphor is 16.1%. The parameters of the obtained w-LEDs are CRI of 81.2 and CCT of 3803 K.