A study of Pr<sub>0</sub><sub>.</sub><sub>7</sub>Sr<sub>0</sub><sub>.</sub><sub>3</sub>Fe<sub>1</sub><sub>-</sub><sub>x</sub>Ni<sub>x</sub>O<sub>3</sub><sub>-δ</sub> as a cathode material for SOFCs with intermediate operating temperature
1 Risø National Laboratory for Sustainable Energy, Technical University of Denmark2 Electrochemistry, Fuel Cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark3 Fuel Cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark4 unknown5 Department of Energy Conversion and Storage, Technical University of Denmark
Pr0.7Sr0.3Fe1-xNxO3-δ (PSFN; x=0.2-0.5) compounds were synthesized and characterized by powder X-ray diffraction (XRD), thermal expansion coefficient (TEC) measurements, electrical conductivity and electrochemical impedance spectroscopy on cone-shaped electrodes on a Ce0.9Gd0.1O1.95 (CGO10) electrolyte. T he main phase of the powders belongs to the orthorhombic crystal system. The conductivities are fairly high, e.g., around 450 scm(-1) at 600 &DEG; C for the x=0.3 compound. The TEC of the compounds is close to the values of ceria-based electrolytes PSEN showed hysteresis in the temperature dependence of the conductivity, TEC and area-specific polarization resistance R-pol. It is considered that the hysteresis was caused by relatively slow adjustment of the oxygen stoichiometry. The electrochemical La0.6Sr0.4Fe0.8Co0.2O3-δ. © 2004 Elsevier B.V. All rights reserved.
Solid State Ionics, 2005, Vol 176, Issue 11-12, p. 1013-1020