Luminescence properties of YAG:Ce~(3+) Nanophosphors prepared by Flame Spray Pyrolysis

摘要

Among the various types of synthesis techniques for phosphors, flame spray pyrolysis (FSP) is a powerful method which is capable of producing particles with good crystallinity and high luminescence efficiency. In this work, we have investigated the influence of the addition of urea and the molar ratio of yttrium to aluminum in the liquid precursor on crystallinity and luminescence properties of YAG:Ce~(3+) nanophosphors prepared by flame spray pyrolysis (FSP) were comparatively studied. The as-prepared YAG:Ce~(3+) nanophosphors by FSP showed hexagonal YAlO_3 and the phase changed to cubic YAG structure after being annealed at 1100℃ for 1hr under atmospheric condition. The heat-treated phosphor particles are spherical shape with an average size blow 50 nm. For FSP, the crystallinity of YAG:Ce~(3+) nanophosphors improved with addition of urea and overloaded aluminum in starting liquid precursor. As a result of XRD result, the nanophosphors from urea-added and slight excess of aluminum in liquid precursor presents higher luminescence intensity than those of from non-urea and less aluminum.