Study of structural and morphological properties of powders and thin films of samaria doped cerium oxide

Abstract

An analysis of 26% samarium doped ceria (SDC) powders and thin films for solid oxide fuel cells (SOFCs) is considered. Glycine-nitrate combustion (CB), co-precipitation (CP), and aqueous sol-gel (SG) methods are used in the preparation of SDC powders and thin films, and methods for analyzing the obtained samples are described. All obtained powders were heated from 200 to 1000℃ degrees , showing that the crystal structure of cerium activated by samarium develops at very high temperatures. It shows that the lattice parameter and crystallite size of the heated powders increase with increasing heating temperature, and the lattice parameter is higher than the theoretical values.

The results of the experiment revealed that the average size of the crystallites of thin films increases with the increase in thickness. Among the applied syntheses, the CB method is considered to have better results compared to co-precipitation and sol-gel methods. The experimental values ​​of the lattice parameter of the thin films deposited on the SiO₂ mat were higher than the theoretical value. As the thickness increases, the average crystallite size of the thin films deposited on the SiO₂ substrate increases. The results of the atomic force microscope showed that the average values ​​of the surface roughness of thin films increase with the increase in thickness. The mean surface roughness (R_s), root mean square roughness (R_q), kurtosis (R_ku), skewness (R_sk) were characterized using appropriate software.