Investigation of Ce0.9Sr0.1Cr0.5Co0.5O3-δ as the anode material for solid oxide fuel cells fueled with H2S

Ce0.9Sr0.1Cr0.5Co0.5O3-delta (CSCrCo) as an anode catalyst was studied in a solid oxide fuel cell (SOFC), where hydrogen sulfide (H2S) was used as fuel. The conductivities were evaluated with a four-probe DC technique in 3 % H-2-N-2 and 5 % H2S-N-2 at 570-800 A degrees C, respectively. X-ray diffraction (XRD) patterns show that CSCrCo powders are fluorite structure which is similar to that of CeO2 parent (JCPDS card no. 34-0394). Meanwhile, CSCrCo anode material has good chemical compatibility with electrolyte (Ce0.8Sm0.2O1.9 (SDC)) in N-2. Through the analysis of XRD and Fourier transform infrared patterns, no other new phase is detected after treatment in 5 % H2S-N-2 at 800 A degrees C for 5 h, which indicate that the material has a good sulfur tolerance. H-2 temperature-programmed reduction and Tafel curves indicate that the temperature of the best catalytic activity is 600 A degrees C. The electrochemical properties of the cell comprising CSCrCo-SDC/SDC/Ag are measured in 5 % H2S-N-2 at low temperatures (500 and 600 A degrees C). The maximal open circuit voltage is 1.04 V, the maximal power density is 12.55 mW cm(-2), and the maximal current density is 40 mA cm(-2) at 500 A degrees C. While at 600 A degrees C, the corresponding values are 0.95 V, 14.21 mW cm(-2), and 90.01 mA cm(-2), respectively. After SOFC operating in 5 % H2S, X-ray photoelectron spectroscopy is used to compare the fresh sample with the H2S-treated one.