A new Pr³⁺-activated molybdate-based phosphor for application to white LEDs with blue excitation

The novel red-emitting phosphors K(x)Sr(1-2x)MoO₄:Pr³⁺(x) (0.00 ≤ x ≤ 0.04) were prepared by solid-state reaction. The crystallization and particle sizes of samples were investigated by powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). TEM images were in good agreement with the theoretical calculation data from the XRD patterns. Photoluminescence analysis indicated that there were three excitation peaks under 430-500 nm, and all samples showed the intensely red emission at 648 nm corresponding to the ³P₀ → ³F₂ transition of Pr³⁺. The concentrations of doping ions, temperature and polyethylene glycol in the phosphor system can significantly influence the intensity of the red emission. The photoluminescence spectral intensity reached its maximum at x = 0.02. The results showed that the investigated phosphor is a potential red phosphor for white light-emitting diodes.