EFFECTS OF LA-DEFICIENCY AND SUBSTITUTION OF FE FOR CO IN SOLID-STATEREACTION BETWEEN LACOO3-DELTA AND AL2O3

The solid-state reaction between La1-xCo1-yFeyO3-delta (x=0.0, 0.1; y= 0.0, 0.5) and Al2O3 was investigated by X-ray diffraction, transmissio n electron microscopy, and electron energy loss spectroscopy, LaAlO3 a nd spinel phases formed from a mixture of LaCoO3 and Al2O3 with the in crease in the reaction temperature, However, substitution of Fe for Co and La-site deficiency in LaCoO3 inhibited the formation of LaAlO3 an d spinel phases, Moreover, the electron diffraction pattern of LaCoO3 after the reaction suggests the possibility that the solid-state react ion enhance the formation of the La-site deficiency of La1-xCoO3.