In order to evaluate potential of PrNi1-xFexO3-δ as new cathode material for solid oxide fuel cells, single phase preparation, crystal structure at various temperatures, thermal expansion property and electrical conduction behavior at high temperature were investigated. Single phase of PrNi1-xFexO3-δ (0.3 ≤ x ≤ 1.0) with orthorhombic distorted perovskite structure was successfully prepared by Pechini method. No structural phase transition was observed between room temperature and 1000°C in air. Linear thermal expansion coefficient was evaluated to be around 1.16 × 10-5K-1, showing fair agreement with that of yttriastabilized zirconia and gadolinia-doped ceria which were frequently employed as electrolyte material. Electrical conductivity of PrNi1-xFexO3-δ increased with increasing Ni content; however, the conductivity did not exceed that of LaNi1-xFexO3-δ. From the comparison of activation energy of variable range hopping conduction and Mössbauer spectroscopy between PrNi1-xFexO3-δ and LaNi1-xFexO3-δ, it was suggested that hole carrier concentration of PrNi1-xFexO3-δ was lower than that of LaNi1-xFexO3-δ owing to variation of valence of Pr ion.
All Science Journal Classification (ASJC) codes
- Ceramics and Composites
- Condensed Matter Physics
- Materials Chemistry