La0.75Sr0.25−xCexCr0.5Mn0.5O3−δ electrode material for symmetric solid oxide fuel cells with H2S-containing fuel

Highlights: •A series of materials La0.75Sr0.25−xCexCr0.5Mn0.5 were synthesized at 1100 °C as potential electrode materials for SFCs. •H2-TPR and O2-TPD indicate that the material with high cerium is more suitable for used as the symmetric electrode. •FTIR results show the material with high cerium content is not resistant to sulfur. •The maximum power density of LSC0.13CM|YSZ|LSC0.13CM cell is 17.86 mW cm−2 for SFC test in 5% H2S–5% wet H2 at 900 °C. -- Abstract: A series of materials La0.75Sr0.25−xCexCr0.5Mn0.5O3−δ (LSCCM, x = 0, 0.1, 0.13 and 0.15) were synthesized by the sol–gel process, and their structures were demonstrated using X-ray diffraction (XRD). The best ratio of ceria-substitution in LSCCM series was studied in detail by H2 temperature programmed reduction (H2-TPR), O2 temperature programmed desorption (O2-TPD), and Fourier transform infrared (FTIR). The catalytic activity results of H2-TPR and O2-TPD prove that ceria-substitution x = 0.15 for La0.75Sr0.25−xCexCr0.5Mn0.5O3−δ has the best catalytic activity, but the FTIR results show the material with high ceria content is not resistant to sulfur. Taking account both catalytic activity and sulfur tolerance, ceria-substitution x = 0.13 is an optimum for La0.75Sr0.25−xCexCr0.5Mn0.5O3−δ, with which maximal power density of 17.86 mW cm−2 can be attained in 5% H2S–5% wet H2 at 900 °C