Enhanced red emitting of LiY(MoO4)2: Sm3+ phosphors by Pr3+ for white LED application

In order to obtain high-efficiency red phosphors to improve the performance of white light-emitting diodes (WLEDs), we prepare a series of single doped and co-doped yttrium lithium molybdate (LiY(MoO4)(2), LYMO) with Sm3+ or Sm3+ and Pr3+ ions red phosphors by solid-state reaction. Structure, chemical components, and morphology of well-crystallized samples were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The LYMO: Sm3+, Pr3+ can efficiently absorb the light from ultraviolet to blue light and has red emissions from 4f-4f transitions of Sm3+. With ultraviolet excitation wavelength 399 nm, white light was observed from individual Sm3+ ion-activated LYMO: Sm3+ phosphors and intensities of its reach a maximum at which concentration of Sm3+ is 3 mol%. More significantly, the low Pr3+ concentration about 0.1 mol% can improve the luminescence intensity of LYMO: 0.03Sm(3+) phosphors and increase drastically the energy transfer efficiency of LYMO: 0.03Sm(3+) phosphors to 16%. Additionally, based on luminescence spectra and decay curves, the energy transfers mechanism from Pr3+ to Sm3+ was discussed. luminescence lifetime The results show that LYMO: Sm3+, Pr3+ can be considered as a potential red-converting materials for WLEDs.