B-site Mo-doped perovskite Pr0.4Sr0.6 (Co0.2Fe0.8)1-xMoxO3-σ (x=0, 0.05, 0.1 and 0.2) as electrode for symmetrical solid oxide fuel cell

Pr0.4Sr0.6(Co0.2Fe0.8)(1-x)MoxO3-sigma (PSCFMx, x = 0, 0.05, 0.1 and 0.2), which obtained by doping molybdenum at the B site of Pr0.4Sr0.6Co0.2Fe0.8O3-sigma (PSCF) cathode, have been synthesized by a solid state reaction method and studied towards the application as symmetrical electrode materials for symmetrical SOFCs (SSOFCs) in this study. It is found that cubic perovskite phase of PSCFM in the Pm/3 m space group is formed after sintered at 1100 degrees C for PSCFMx (x = 0, 0.05 and 0.1) samples, and the main phase is converted to K2NiF4 structure identified as SrPrFeO4 in the 14/m space group, and some new phases of Pr2O3 and CoFe-alloy appear after PSCFMx is heat-treated in dry H-2 at 900 degrees C for 2 h. The K2NiF4 structure SrPrFeO4 can be transferred to a pure cubic structure of PSCFMx again by calcining it in air at 900 degrees C. The maximum power densities of a single SSOFC based on the PSCFM0.05 symmetrical electrode, which shows the lowest polarization resistances (R-p), are 493 and 160 mW cm(-2) at 850 degrees C in H-2 and CH4, respectively. No obvious degradation is observed during a 100 h stability test in CH4, which suggests that PSCFM material is a potential symmetrical electrode for SSOFCs. (C) 2014 Elsevier B.V. All rights reserved.