SYNTHESIS OF NANOCRYSTALLINE COMPOSITE OXIDES LA1-XSRXFE1-YCOYO3 WITHTHE PEROVSKITE STRUCTURE USING POLYETHYLENE GLYCOL-GEL METHOD

Precursors to La1-xSrxFe1-yCoyO3 have been prepared using polyethylene glycol as a protecting agent of colloidal particles via the sol-gel p rocess. After the solid phase reaction at 500-600-degrees-C for 2 h, n anocrystalline composite oxides La1-xSrxFe1-yCoyO3 (x = 0.0, 0. 1, 0.2 , 0.4; y = 0.1, 0.2, 0.5, 0.6. 1.0) were obtained. The effects of vari ous conditions of the synthesis processes on the products containing t he various components and the preparation processes of nanocrystalline composite oxides by the direct heat decomposition method are reported . The results indicate that the solid phase reaction can be completed at a lower temperature and with a shorter reaction time. and that it h as a direct relationship to the distribution of the various components in the precursors.