Abstract
SmAlO3 was synthesized by the TW method. As the starting solution, each aqueous solution of Al(NO3)39H2O and Sm(NO3)36H2O was dissolved in proper amount of distilled water. Various quantities of Si(OC2H5)4)(TEOS) and a small amount of 2M-HCl as catalysis were mixed into the starting solution. In a sample obtained by heating the gel with TEOS of 0.90×10-2 mol for 30 min, pure SmAlO3 in a single phase was not obtained at the temperature of 1100°C, because the obtained sample had each small amount of SmO and β-Cristobalite liberated from SmSiO3. It was thought that SmAlO3 was formed as a degradation product of Sm4Al2O9, simultaneously as a product of the reaction of γ-Al2O3 and Sm2O3 in the progress of its decomposition when the decomposition of SmSiO3 proceeded in preference to the degradation of Sm4Al2O9. From comparison of their X-ray diffraction patterns for samples with two kinds of TEOS content consisting of 1.35×10-2 mol and 0.90×10-2 mol, it was thought that α-Al2O3 was transformed into γ-Al2O3.
