Sol-gel based YAG:Tb~(3+), Ce~(3+), Eu~(3+) phosphors for application in lighting sources

摘要

Yttrium aluminates based on the system Y_2O_3-Al_2O)3 are well known as important class of materials for advanced optical technologies [1,2]. Among them the composition 3Y_2O_3-5Al_2O_3 commonly called yttrium aluminum garnet (YAG) exhibits outstanding luminescence properties when doped with a lanthanide or transition elements leading to attractive phosphors for applications in flat panel displays (FPDs), solid state laser materials, x-rays detectors for miorotomography and light emitting diodes-based fluorescent lamps. Since the solid-state synthesis of YAG ceramics from aluminum and yttrium oxides requires high sintering temperatures (above 1600°C) [3,4], it is difficult to control both the homogeneity and purity of YAG powders through such synthesis conditions. Furthermore it has been shown that features like phase control, homogeneity, purity as well as luminescence efficiency, are strongly dependant on the synthesis route [5-7], Therefore, so as to provide a high quality material at lower temperature, we have undertaken to prepare YjAlsOn by a wet chemical way, the sol-gel process.