Influence of annealing temperature on the grain growth of samarium-doped ceria

Samarium-doped ceria (SDC) can be used as electrolyte of solid oxide fuel cells (SOFCs). In this study, SDC films have been deposited by E-beam evaporation at room temperature (RT) and 200 °C, and then annealed at 500, 600, 700, and 800 °C. The structure and morphology of samples were analyzed by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). Initial temperature for deposition of SDC films at RT and 200 °C, respectively, is shown to be critical with respect to crystallinity, texture coefficient, grain size, smoothness and morphology. The SDC film as deposited at RT is amorphous and extremely smooth. Whereas, the SDC film as deposited at 200 °C is crystalline, has a faceted surface, average grain size of 14 nm, arrow-head morphology, and no porosity. Generally, after annealing from 500 to 800 °C for both types of films, the grain size is shown to increase with increasing temperature and the development of pores is noted.