Ceria-based Nanoceramics by Flash Sintering

Ceria-based ceramics can be considered the most promising solid electrolyte materials for Intermediate Temperature Solid Oxide Fuel Cells (IT-SOFCs). In this work, nanocrystalline ceria nanopowders doped with 10 mol% gadolinium or 10 mol% samarium were synthesized by co-precipitation using ammonia solution as precipitating agent. Upon a simple calcination step at 400°C, necessary to remove residual water and to complete the crystallization of fluorite single phase, the synthesized nonopowders were used as starting materials in flash sintering experiments for producing solid bodies at temperatures always lower than 700°C. By varying the electric field applied upon sintering, different shrinkage behaviour and microstructures were obtained. The electrical characterization revealed ionic conductivity similar to data reported in the literature, for similar materials obtained by traditional sintering at higher temperature.