Gd-doped ceria (GDC) is a promising solid electrolyte for intermediate temperature solid oxide fuel cells (IT-SOFCs) due to its high oxygen-ion conductivity. However, commercialization is limited due to high grain boundary resistance and electronic conduction in reduced conditions. In this work, Al- and Mn-added GDCs were designed to overcome their weaknesses. GDC and Al- and Mn-added GDC powders were prepared using spray pyrolysis and then sintered using spark plasma sintering technique to obtain dense ceramic pellets. Additives enhanced the sinterability of the ceria leading to an increase in ionic conduction. More importantly, electronic conduction in GDC with the additives was suppressed under reduced conditions. This demonstrates that Al- and Mn-added GDC is a possible candidate as a solid electrolyte for IT-SOFCs.

Keywords: GDC, Additives, Ionic conduction, Electronic conduction