PrNi0.6Co0.4O3–Ce0.8Sm0.2O1.9 composite cathodes for intermediate temperature solid oxide fuel cells

Cobalt-containing perovskite, PrNi0.6Co0.4O3 (PNC) has been investigated as a possible candidate for cathode material for intermediate temperature solid oxide fuel cells. It is found that the maximum and minimum electrical conductivity of PNC are 1580 S cm−1 at 50 °C and 1031 S cm−1 at 1000 °C, respectively. The thermal expansion coefficient (TEC) of the PNC is 14.21 × 10−6 K−1 at 700 °C. The TEC of the PNC–50 wt.% Ce0.8Sm0.2O1.9 (PNC–50SDC) composite cathode is 13.49 × 10−6 K−1 at 700 °C, which is much more matching with the other components within the cell. The cathodic polarization of the single-phase PNC and composite cathodes with SDC shows that a weight ratio between PNC and SDC of 50:50 yields the lowest area specific resistance of 0.097 Ω cm2 at 600 °C and 0.031 Ω cm2 at 700 °C. The maximum power density of the PNC–50SDC cathode in an anode-supported SOFC is 1.09 W cm−2 at 700 °C.

► The electrical conductivity of the PNC is 1031 S cm−1 at 1000 °C.
► The TEC of the PNC–50SDC cathode is 13.49 × 10−6 K−1 at 700 °C.
► The ASR of PNC–50SDC yields the lowest value of 0.031 Ω cm2 at 700 °C.
► The maximum power density of the PNC–50SDC cathode is 1.09 W cm−2 at 700 °C.