H2S tolerance effects of Ce0.8Sm0.2O2−δ modification on Sr0.92Y0.08Ti1−xNixO3−δ anode in solid oxide fuel cells

[Display omitted] Sr0.92Y0.08Ti1−xNixO3−δ (SYTN) was investigated in the presence of H2S containing fuels to assess the feasibility of employing oxide materials as alternative anodes. Aliovalent substitution of Ni2+ into Ti4+ increased the ionic conductivity of perovskite, leading to improved electrochemical performance of the SYTN anode. The maximum power densities were 32.4 and 45.3mW/cm2 in H2 at 900°C for the SYT anode and the SYTN anode, respectively. However, the maximum power densities in 300ppm of H2S decreased by 7% and by 46% in the SYT and the SYTN anodes, respectively. To enhance the sulfur tolerance and to improve the electrochemical properties, the surface of SYTN anode was modified with samarium doped ceria (SDC) using the sol-gel coating method. For the SDC-modified SYTN anode, the cell performance was mostly recovered in the pure H2 condition after 500-ppm H2S exposure in contrast to the irreversible cell performance degradation exhibited in the unmodified SYTN anode.