The KEu(WO4)2 Red Phosphor Co-doped with Li+ and SO42− for Synergistic Enhancement of High Efficiency and Thermal Stability
摘要
A series of tungstate red phosphors K1−xLixEu(WO4)2−y(SO4)y were successfully prepared by sol-gel method, and the effects of the introduction of Li+ and SO42− on the fluorescence intensity and thermal quenching properties of the prepared K1−xLixEu(WO4)2−y(SO4)y phosphors were investigated. The X-ray diffraction data show that the prepared (Li+ and SO42−)-doped KEu(WO4)2 phosphors have a monoclinic tetragonal structure. In addition, the emission intensities of all the observed emission peaks change significantly with the increase of Li+ doping concentration, especially the intensity of the emission peaks at 615 nm fluctuated significantly and reached the maximum at x = 0.3 and y = 0.2. The K1−xLixEu(WO4)2−y(SO4)y phosphors are found to have the highest fluorescence intensity at x = 0.3 and y = 0.2. Moreover, the K0.7Li0.3Eu(WO4)1.8(SO4)0.2 phosphor has better thermal quenching properties and luminescence efficiency, and the experimental results indicates that the fluorescence intensity and thermal burst performance of KEu(WO4)2 red phosphor could be effectively improved by using low-cost bionic doping of Li+ and SO42−.