Ce0.9Sr0.1Cr0.5Fe0.5O3−δ as the anode materials for solid oxide fuel cells running on H2 and H2S

Ce0.9Sr0.1Cr0.5Fe0.5O3−δ (CSCrF) powders were synthesized by gel combustion method and the conductivities have been evaluated with DC four-probe method in 3% H2–N2 and 5% H2S–N2 at 400–800 °C, respectively. XRD shows that CSCrF powders have cubic perovskite structure which is similar to that of CeCrO3 (JCPDS card No. 75-0289). Meanwhile, CSCrF exhibits good chemical compatibility with electrolyte (Ce0.8Sm0.2O1.9) in N2. Through analysis of XRD and IR, some Ce0.9Sr0.1Cr0.5Fe0.5(O, S)3−δ are produced after exposure to 5% H2S–N2 at 800 °C for 5 h, which has a resemblance to Refs. [1] and [2]. The electrochemical properties were measured for the cell comprising CSCrF–Sm0.2Ce0.8O1.9/Sm0.2Ce0.8O1.9/Ag in 5% H2S at low temperature (450, 500, 550 and 600 °C), and in 3% H2–N2 at 500 °C, respectively. Electrochemical impedance spectroscopy (EIS) and the equivalent circuit reveal that polarization resistance is the main reason affecting the performance of the cell at low temperature. The area specific resistance significantly decreases with the increasing temperature.

► Luo et al. have evaluated the performance of Ce0.9Sr0.1Cr0.5V0.5O3−δ as a anode in SOFCs based on YSZ electrolyte. However, the vanadium-based anode often is toxicity to health and higher cost. Therefore, more attention should be paid to find low toxicity and cheaper transitional metals replacing V-based compounds, such as Fe-based. In this study, a novel anode powders Ce0.9Sr0.1Cr0.5Fe0.5O3−δ (CSCF) was synthesized as materials for solid oxide fuel cell. The research reported that Ce0.9Sr0.1Cr0.5Fe0.5O3−δ (CSCF) has high electrical conductivity in 3% H2 and 5% H2S, reasonable oxide ionic diffusivity and lower polarization resistance. To the best of our knowledge, the performance of Ce0.9Sr0.1Cr0.5Fe0.5O3−δ anode based on Sm0.2Ce0.8O1.9 (SDC) electrolyte in SOFCs has not been reported to date.