摘要
A series of Eu2+ and Sm3+ co-doped Li2SrSiO4 phosphors are prepared by the high temperature solid-state reaction. The morphology, structure and spectroscopic properties of the prepared samples are characterized by scanning electron microscopy, X-ray diffraction, diffuse reflection spectra, photoluminescence spectra and electron paramagnetic resonance spectra, respectively. The effect of Sm3+ doping concentration on the photoluminescence intensity of the prepared samples is also investigated. The results indicate that the crystal structure of Li2SrSiO4 is not changed with the Eu2+, Sm3+ co-doping. The spherical-like particle size of the obtained product is about 20-30聽nm in diameter. When the Sm3+ concentration is 0.3聽mol%and the Eu2+ concentration is 0.7聽mol%, the phosphors show the maximum emission intensity, which is 50%higher than that of Eu2+ doped Li2SrSiO4. Excited at 420聽nm, the phosphor presents a single broad emission band peaking at 558聽nm, which is ascribed to the 4f65d1聽鈫捖?f7 transitions of Eu2+ and 4G5/2聽鈫捖?sup>6H5/2 and 4G5/2聽鈫捖?sup>6H7/2 transitions of Sm3+. The Commission International de I鈥睧clairage chromaticity coordinates of Li2SrSiO4:0.7聽mol%Eu2+, 0.3聽mol%Sm3+ are x聽=聽0.28, y聽=聽0.28.