Co-infiltrating Pr0.6Sr0.4FeO3-Ce1-xPrxO2(x=0.1, 0.3, 0.5, 0.7, 0.9) mixed oxides into the La0.9Sr0.1Ga0.8Mg0.2O3 skeleton for use as low temperature solid oxide fuel cell cathodes

Here, first time, Pr0.6Sr0.4FeO3-Ce1-xPrxO2 (x = 0.1, 0.3, 0.5, 0.7, 0.9) dual-phase composites are co-infiltrated into the porous La0.9Sr0.1Ga0.8Mg0.2O3 (LSGM) skeletons to form composite cathodes and are used for low temperature solid oxide fuel cell (SOFC). By optimizing mass ratios of Pr0.6Sr0.4FeO3/Ce1-xPrxO2 and doping contents of Pr in the Pr0.6Sr0.4FeO3-Ce1-xPrxO2 composites, the lowest polarization resistance (Rp) recorded at 550 °C is achieved as 0.246 Ωcm2 for the 50wt%Pr0.6Sr0.4FeO3-50wt% Ce0.1Pr0.9O2-LSGM composite cathode. Reduction of both chemical resistance and charge transfer resistance are proved to be responsible for the performance improvement. Thermal cycling test reveals a performance degradation of only 4.6% for the 50wt%Pr0.6Sr0.4FeO3-50wt% Ce0.1Pr0.9O2-LSGM composite cathode after five thermal cycles, thereby showing a good thermal expansion match between the 50wt%Pr0.6Sr0.4FeO3-50wt%Ce0.1Pr0.9O2 composite and the LSGM skeleton. A functional fuel cell with infiltrated Ni/Ce0.8Sm0.2O2 (Ni/SDC) as anode and infiltrated 50wt%PSF-50wt% Ce0.9Pr0.1O2 as cathode shows the maximum power densities of 1.172, 0.916, 0.519 and 0.196 Wcm−2 at 600, 550, 500 and 450 °C, respectively. The cell operates at 550 °C with an almost constant current density of 1.087A/cm2 at 0.7 V for 50 h, demonstrating good stability.