Synthesis of novel Dy³⁺-activated LiSrBiTeO₆ phosphors for white light-emitting diodes

Novel yellow-light-emitting LiSrBiTeO_6: xDy³⁺ (x = 0.005, 0.01, 0.02, 0.05, 0.10, 0.20, 0.30, and 0.40) phosphors were synthesized. X-ray diffraction (XRD) results revealed that the prepared LiSrBiTeO₆:Dy³⁺ phosphors are hexagonal structure. The luminescence properties showed that the phosphor can be effectively excited by UV light (388 nm) and exhibits bright emission centered at 484, 575, and 663 nm, attributed to the ⁴F_9/2→⁶H_15/2, ⁴F_9/2→⁶H_13/2, and ⁴F_9/2→⁶H_11/2 transitions of Dy³⁺ ions, respectively. The optimum dopant concentration of Dy³⁺ ions in LiSrBiTeO₆:xDy³⁺ was around 10 mol% and the critical transfer distance of Dy³⁺ was calculated as 14 Å. The CIE color coordinates fall into the yellow-light region. The developed phosphor has great potential as a yellow-light-emitting phosphor for UV-light-emitting diodes. (paper)