La0.7Ca0.3CrO3–Ce0.8Gd0.2O1.9 composites as symmetrical electrodes for solid-oxide fuel cells

La0.7Ca0.3CrO3 (LCC)–Ce0.8Gd0.2O1.9 (GDC) composites have been investigated as symmetrical electrodes for solid-oxide fuel cells (SOFCs) on La0.9Sr0.1Ga0.8Mg0.2O3−δ (LSGM) electrolyte, where there is no interlayer between anode and electrolyte. LCC oxide is chemically compatible with GDC and LSGM electrolyte at temperatures up to 1200 °C. The electrical conductivity of the LCC–GDC composites decreases with increasing GDC content. The best electrical conductivities of 18.64 S cm−1 in air and 1.86 S cm−1 in H2 at 850 °C are achieved for an 80 wt% LCC–20 wt% GDC (LCC–GDC20) composite. The thermal expansion coefficients of the LCC–GDC composites increase with increasing GDC content, and are very close to that of the LSGM electrolyte. A cell with a 0.3 mm thick LSGM electrolyte and LCC–GDC20 symmetrical electrodes displays the highest electrochemical performance. The maximum power density is 573 mW cm−2 in dry H2 and 333 mW cm−2 in humidified commercial city gas containing H2S at 900 °C, respectively. These results suggest that the LCC–GDC20 composite can potentially serve as an electrode for symmetrical SOFCs operated on H2 and commercial city gas containing H2S.