Redox stability and sulfur resistance of Sm0.9Sr0.1CrxFe1−xO3−δ perovskite materials

Abstract

Abstract Sm 0.9 Sr 0.1 Cr 0.5 Fe 0.5 O 3−δ was used as a promising anode catalyst for the conversion of H 2 S-containing fuel by SOFC in our previous research. A further research about the redox stability and sulfur resistance of the series of Sm 0.9 Sr 0.1 Cr x Fe 1− x O 3−δ ( x = 0.2, 0.5, 0.8) was carried out through XRD, TEM, BET, and H 2 -TPR in this work. It was found the different doping amount of SSCF were stable at the temperature below 800 °C under reduction conditions. XPS was used to compare the fresh sample with the treated one. The reduction treatment tended to decrease the concentration of lattice oxygen but the surface adsorbed oxygen amount was found to be higher in reduced samples comparing with fresh samples. It was suggested that these materials had tendency to recapture oxygen when exposed to air after reduction. The role of lattice oxygen in deactivation of SSCF as anode catalyst was also studied after the sample was reduced to 1000 ppm H 2 S (balanced by N 2 ) at 800 °C for 2 h.