Abstract
CaTi0.6-xFe0.4PxO3-δ (0≤x ≤ 0.75) perovskite series are investigated as potential symmetrical electrodes for SOFCs. Pure phase compounds with a cubic perovskite structure (s.g. Pm3̅m ) are obtained for x ≤ 0.025, while higher doping level leads to the formation of Ca10(PO4)6(OH)2 as secondary phase. The P-doped compounds are structurally stable under reducing atmosphere unlike the undoped phase. Conductivity values of the P-doped samples are slightly higher than that of the undoped one, i.e. 0.11 and 0.07 Scm−1 for CaTi0.575Fe0.4P0.025O3-δ and CaTi0.6Fe0.4O3-δ, respectively, at 750 °C in air. The performance of CaTi0.575Fe0.4P0.025O3-δ acting simultaneously as both anode and cathode was also tested in a symmetrical solid oxide fuel cell with a 240 μm thick YSZ electrolyte. Hence, these results show that PO43- units can be introduced into CaTi0.6Fe0.4O3-δ perovskite structure, having beneficial effects on the electrochemical performance and the phase stability.
Original language | English |
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Article number | 155437 |
Journal | Journal of Alloys and Compounds |
Volume | 835 |
Early online date | 30 Apr 2020 |
DOIs | |
Publication status | Published - 15 Sept 2020 |
Keywords
- Calcium titanates
- Oxyanion doping
- Phosphate
- Symmetrical solid oxide fuel cell
ASJC Scopus subject areas
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry