Síntese de silicato de lantânio tipo apatita pelo método sol-gel utilizando silicato de sódio como fonte de sílica

Abstract

Ceramics of lanthanum silicate apatite-type have been studied with great technological interest at IT-SOFC applications (Intermediate Temperature Solid Oxide Fuel Cell) for having good ionic conductivity at intermediate temperatures (600-800°C), higher than that of YSZ (Ytria Stabilized Zirconia) in high-temperature SOFCs. At this work has made the synthesis of the lanthanum silicate apatite-type from Na2SiO3 as a source of silica by the modified sol-gel method that allowed the formation of ceramic powders of lanthanum silicate apatite-type in calcination temperature at 900°C, which is much lower than those other methods of synthesis. Analysis by x-ray diffraction (XRD) showed the lanthanum silicate apatite-type phase as the main phase. Scanning electron microscopy was used to nanometric powders observation.