Abstract

Undoped CeO2, co-doped and tri-doped CeO2 with Si, Si-Al and Si-Fe, were prepared by sol-gel method. Nanoparticles with an average crystal size of 2-10 nm, were obtained and structurally characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Powders were compacted by uniaxial pressure and sintered in air at 1250 °C to obtained sintered pellets. The different compositions maintained the cerianite crystal structure, implying that dopant elements enter in the structure forming a solid solution, although some segregation was observed by SEM and TEM analysis in pellets. The undoped CeO2 material reached a relative density of 0.95 % at 1250°C while doped samples presented variations in this value and grain size and relative density, clearly attributed to doping. According to these results, these materials could have potential applications in solid oxide fuel cells, electrodes and sensors.