Filling the Cyan Gap in wLEDs with Ba 2 MgWO 6 :Bi 3+ Solid Solution for Full-Spectrum LED Illumination

A novel cyan-emitting solid solution phosphor Ba 2 MgWO 6 :0.003Bi 3+ , 0.025[Ga 3+ -Ga 3+ ] (BMWO) was prepared by high-temperature solid-phase reaction using a cation-pair substitution strategy. The phase structure was carefully analyzed by x-ray diffraction (XRD) and Rietveld refinement, and the origin of the cyan emission in samples was explained by combination with photoluminescence (PL) analysis. Density functional theory (DFT) calculations revealed that the BMWO host has spin symmetry, with a bandgap value of 2.8544 eV, which increases to 3.68 eV after doping with 0.003Bi 3+ , and to 3.66 eV after the introduction of 0.025[Ga 3+ -Ga 3+ ] cation-pair units. The BMWO: x Bi 3+ samples showed broad emission with a peak at 497 nm under ultraviolet (UV) excitation at 312 nm. The cyan emission intensity of the solid solution phosphor formed by the introduction of [Ga 3+ -Ga 3+ ] cation-pair units was increased by a factor of 3. The results suggest that the solid solution construction method using cation-pair unit substitution can be used to optimize the photoluminescence performance of the phosphors, and that the novel cyan-emitting BMWO:0.003Bi 3+ , 0.025[Ga 3+ -Ga 3+ ] solid solution phosphors have the potential for use in white light-emitting diodes (wLEDs) and anti-counterfeiting applications.