Tunable single-phased white-emitting Sr3Y(PO4)3:Dy3+ phosphors for near-ultraviolet white light-emitting diodes

Single-component white-emitting Sr3Y(PO4)3:Dy3+ phosphors were synthesized by a high-energy deformation process. X-ray diffraction patterns showed the resulting crystallized phase to be of cubic structure, space group I-43d (no. 220). The broad-band excitation spectra between 250 and 500 nm were observed by monitoring the emission wavelength at 576 nm, which matches well with commercial near-UV or blue LED chips. Under a 352 nm excitation, the emission peaks were observed at 483 nm (blue), 576 nm (yellow), and 666 nm (red), corresponding to the 4F9/2 → 6H15/2, 4F9/2 → 6H13/2, and 4F9/2 → 6H11/2 transitions of Dy3+ ions. The optimized doping concentration of Dy3+ ion was 8 mol%. By controlling the Dy3+ ion concentration, tunable colors from white to yellow were obtained in Sr3Y(PO4)3:Dy3+ phosphors. These results reveal that studied materials may be a promising candidate for white LED applications.