A novel bismuth-activated Sr₃NaSbO₆ phosphor with multi-band switchable emission for NUV-pumped LEDs

Multi-band emission characteristics open up more possibilities for the application of phosphors in LEDs. In this work, a novel Bi³⁺-activated Sr₃NaSbO₆ phosphor is developed. The Bi³⁺ occupation, luminescence properties and application in LEDs of the phosphor are investigated and discussed. There are Sr and Na sites in the crystal structure for Bi³⁺ substitution, corresponding to two different luminescence centers, which can be excited by commercial UV chips. By changing the excitation wavelength, Bi³⁺ in the two lattice sites can be excited separately, and a switchable multi-band emission can be obtained accordingly. The blue emission peaks at 450 nm, and the other emission has an ultra-wide full-width at half-maximum of 206 nm, which can cover a wider visible spectrum. All the results show that the phosphor has application prospects in LEDs.