Authors: D. Jia, C.V. Shaffer, J.E. Weyant, A. Goonewardene, X. Guo, Y. Wang, X.Z. Guo, K.K. Li, Y.K. Zou and W. Jia
Affilation: Boston Applied Technologies, Inc., United States
Pages: 339 - 342
Keywords: salted sol-gel, nanophosphor, YAG:Ce
Nanophosphors of Y3Al5O12:Ce3+ (YAG:Ce) were synthesized with a salted sol-gel (SSG) method, in which water-Heptane solutions of certain inorganic salts were used along with traditional metal alkoxides precursors. YAG phase could be formed at a temperature below 800ºC. Nanoparticles of YAG heat-treated at 900ºC for 10 hours were obtained. The size of the nanoparticles varied from 30 nm to 120 nm. There was no significant size growth at higher temperature heat treatment. X-ray diffraction spectrum of samples sintered at different temperatures was measured. It was found that the intensities of x-ray diffraction peaks reached a maximum value when sintered at about 1350ºC. Compared with the corresponding temperatures of 1500ºC and >1600ºC for those fabricated via solid-state reactions with and without a flux, BaF2, the sintering temperature was much reduced for this method. Concentration and temperature dependence of the luminescence intensity were measured. Compared with the samples prepared by solid-state reactions, no obvious differences were observed, indicating that no additional quenching mechanisms, such as surface quenching, were introduced into the nanostructured YAG:Ce. Furthermore, the luminescence intensity was found at least 20% higher than those of materials synthesized via direct solid-state reactions due to the better crystallinity obtained by the SSG method.