Enhanced electrochemical performance of the YBa0.5Sr0.5Co1.4Cu0.6O5+δ cathode material by Sm0.2Ce0.8O1.9 incorporation for solid oxide fuel cells application

The performance of YBa0.5Sr0.5Co1.4Cu0.6O5+δ(YBSCCO)–Sm0.2Ce0.8O1.9 (SDC) composite cathode for SOFC is investigated in this paper. YBSCCO and SDC oxides are synthesized by the sol–gel method. The XRD result reveals that no obvious chemical reaction occurs after sintering the mixture of the YBSCCO and SDC at 850 °C for 20 h. The thermal expansion behavior shows that the YBSCCO–xSDC composite cathode has the suitable TEC values (13.3–11.2 × 10−6 K−1) for the common electrolyte. In different proportions of the composite cathode, YBSCCO–30SDC shows the lowest polarization resistance values, which are only about 0.022 Ω cm2 at 850 °C and 0.034 Ω cm2 at 800 °C. The electrolyte-supported single cell using YBSCCO–30SDC cathode is fabricated, and the peak power densities values are 567 and 432 mW cm−2 at 850 and 800 °C, respectively.