Preparation and photoluminescence of LiSrBO3:Eu3+ red-emitting phosphors for white leds

Abstract

LiSrBO3:xEu3+ phosphors were synthesized by conventional solid-state reaction and were systematically characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and photoluminescence spectroscopy. The excitation and emission spectra reveal that the LiSrBO3:Eu3+ phosphor can be effectively excited by ultraviolet (395 nm) and blue (466 nm) light and exhibits a satisfactory red performance which peaked at around 612 nm corresponding to the 5D0 → 7F2 transitions of Eu3+. The concentration quenching mechanism was verified to be a dipole–dipole interaction. The dopant R+ (R+ = Li+, Na+ and K+) as charge compensator can further enhance luminescence intensity, and the emission intensity of the phosphor doped Li+ is higher than that doped with Na+ or K+. Introduction of Al3+ reduced the symmetry of the crystal field and increased the emission of 612 nm (5D0 → 7F2), which improved the chromaticity coordinates of LiSrBO3: Eu3+ phosphor.