Cobalt–free La0.5Sr0.5Fe0.9Mo0.1O3–δ electrode for symmetrical SOFC running on H2 and CO fuels.

Cobalt–free perovskite La 0.5 Sr 0.5 Fe 0.9 Mo 0.1 O 3– δ (LSFMo) was evaluated as the electrode of symmetrical SOFC (S–SOFC) using H 2 and CO as fuels. XRD results demonstrate that the LSFMo electrode is redox stable at a temperature below 800 °C. Furthermore, the chemical compatibility of LSFMo electrode with both Sm 0.2 Ce 0.8 O 1.95 (SDC) and La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 3–δ (LSGM) electrolytes was assessed. The thermal expansion coefficients (TECs) of the LSFMo at 30–850 °C are 13.4 × 10−6 K−1 in air and 15.1 × 10−6 K−1 in 5% H 2 /Ar. However, for the pre–reduced LSFMo, the TEC in 5% H 2 /Ar decreases to 11.8 × 10−6 K−1. Using LSFMo as symmetrical electrode of S–SOFCs, the maximum power densities (P max) of 562 mW cm−2 in dry H 2 and 474 mW cm−2 in dry CO at 750 °C are attained based on 300 μm thick SDC electrolyte, while based on the LSGM electrolyte with same thickness, the P max attain 508 mW cm−2 in dry H 2 and 379 mW cm−2 in dry CO. For the LSGM supported S–SOFC, the total polarization resistances (R p) attain 0.460 Ω cm2 in dry H 2 and 1.099 Ω cm2 in dry CO at 750 °C. Additionally, the S–SOFCs with LSFMo electrode exhibit good power cycling stability, long–term stability and multiple redox and thermal cycling stability. Above results indicate that the LSFMo material is a very potential symmetrical electrode for S–SOFCs. • LSFMo was evaluated as electrode of S–SOFCs with SDC/LSGM electrolytes. • LSFMo electrode is redox stable at IT-SOFC operating temperatures. • LSFMo electrode exhibits good thermal expansion match with SDC/LSGM electrolytes. • Good electrochemical performances for S–SOFCs with LSFMo electrode were obtained. • Excellent cell stability for S–SOFCs with LSFMo electrode was obtained. [ABSTRACT FROM AUTHOR]