Thermomechanical and Electrical Properties of Pr1 –xSrxFe0.8Co0.2O3 (x = 0.3 and 0.4) and Composites Based on Them

• Published in: Inorganic materials 2021-03, Vol.57 (3), p.316-323
• Main Authors: Nikonov, A. V., Pavzderin, N. B., Khrustov, V. R., Semenova, I. V., Kuterbekov, K. A., Bekmyrza, K. Zh
• Format: Article
• Language: English
• Subjects: Cathodes; Chemistry; Chemistry and Materials Science; Composite materials; Electrical properties; Electrical resistivity; Electrode materials; Electrolytes; Electrolytic cells; Industrial Chemistry/Chemical Engineering; Inorganic Chemistry; Materials Science; Self propagating high temperature synthesis; Sintering (powder metallurgy); Solid oxide fuel cells; Strontium zirconates; Thermal expansion; Thermomechanical properties; Yttria-stabilized zirconia
• ISSN: 0020-1685; 1608-3172
• DOI: 10.1134/S0020168521030110

— Pr 1 – x Sr x Fe 0.8 Co 0.2 O 3 (PSFC) ( x = 0.3, 0.4) materials and composites based on them are thought to be promising cathode materials for solid oxide fuel cells. The PSFC powders with micron-sized particles were prepared by self-propagating high-temperature synthesis. Zr 0.84 Y 0.16 O 2 – δ (YSZ) and Ce 0.73 Gd 0.27 O 2 – δ (GDC) nanopowders were used as a second component of the composites. It was found that at 1000°C PSFC reacts with the YSZ electrolyte to form SrZrO 3 , whereas there is no chemical interaction with GDC even at 1200°C. The electrical conductivity of the PSFC with x = 0.4 has been shown to be more than twice that of the material with x = 0.3. Herewith the increase of the Sr concentration in the PSFC leads to an increase of its thermal expansion coefficient (TEC), which exceeds that of GDC. The formation of PSFC/GDC composites makes it possible to achieve a better match in thermal expansion and sintering kinetics between the cathode and electrolyte materials. However, the electrical conductivity of the studied composites is a factor of 2–5 lower than that of the initial PSFC materials.