Ce0.9Sr0.1VOx (x = 3, 4) as anode materials for H2S-containing CH4 fueled solid oxide fuel cells

✍ Scribed by Nemanja Danilovic; Jing-Li Luo; Karl T. Chuang; Alan R. Sanger

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 991 KB
• Volume: 192
• Category: Article
• ISSN: 0378-7753
• DOI: 10.1016/j.jpowsour.2009.03.045

✦ Synopsis

The stability and activity in 0.5% H 2 S-CH 4 of Ce 0.9 Sr 0.1 VO 3 and Ce 0.9 Sr 0.1 VO 4 anode materials for H 2 Scontaining CH 4 fueled SOFCs have been determined. XRD showed that Ce 0.9 Sr 0.1 VO 4 was reduced when the fuel gas was 0.5% H 2 S-CH 4 , while Ce 0.9 Sr 0.1 VO 3 remained stable over 24 h at 950 • C. Electrochemical tests in 0.5% H 2 S-CH 4 showed stable performance at 950 and 800 • C for cells comprising Ce 0.9 Sr 0.1 VO 3 |YSZ|Pt. Comparison of fuel cell performances using 0.5% H 2 S-CH 4 , 0.5% H 2 S-N 2 and 5% H 2 S-N 2 as feeds showed that Ce 0.9 Sr 0.1 VO 3 was not active for oxidation of methane, but highly active for conversion of H 2 S. Electrochemical impedance results were consistent with the finding that the anode was activated only in an environment that contained H 2 S. Conductivity measurements showed there was an increase in conductivity in H 2 S-containing environments, and that this increase resulted from a change in composition and structure from the oxide to monoclinic Ce 0.9 Sr 0.1 V(O,S) 3 , as evidenced by XPS and XRD analyses.