Synthesis of (Sr 0.85Zn 0.15) 3(PO 4) 2:Eu 3+ by a modified solid-state reaction and its luminescent properties for ultraviolet light emitting diodes

Abstract

Using urea, boric acid and polyethylene glycol (PEG) as auxiliary reagents, the novel red emitting phosphors (Sr 0.85Zn 0.15) 3(PO 4) 2:Eu 3+ have been successfully synthesized by a modified solid-state reaction. The material has potential application as a fluorescent material for ultraviolet light-emitting diodes (UV-LEDs). The dependence of the properties of (Sr 0.85Zn 0.15) 3(PO 4) 2:Eu 3+ phosphors upon urea, boric acid and the PEG concentration and the quadric sintered temperature were investigated. The crystallization and particle sizes of (Sr 0.85Zn 0.15) 3(PO 4) 2:Eu 3+ have been investigated by using powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). Luminescent measurements showed that the phosphors can be efficiently excited by ultraviolet (UV) to visible region, emitting a red light with a peak wavelength of 616 nm. The results show that the boric acid, urea and the PEG were effective in improving the fluorescent intensity of (Sr 0.85Zn 0.15) 3(PO 4) 2:Eu 3+ and the optimum molar ratio was 0.1, 8 and 0.021, respectively.