A solid oxide fuel cell operating on hydrogen sulfide (H2S) and sulfur-containing fuels

A new class of materials based on LaxSr1-xVO3-delta (LSV) has been studied as the anode for solid oxide fuel cells (SOFCs) operating on H2S-containing fuels. The LSV-based anodes are chemically and electrochemically stable under SOFC operating conditions. Furthermore, they appear to be active towards the preferential oxidation of H2S over hydrogen, as suggested by open circuit voltage, impedance spectra, and cell performance measurements using various H2S and H-2 fuel mixtures. A system with configuration LSV/YSZ/LSM-YSZ showed a maximum power density of 90 mW/cm(2) at 220 mA/cm(2) with a 5% H2S-95% N-2 fuel mixture at 1273 K. This same cell configuration showed a maximum power density of 135mW/cm(2) at 280mA/cm(2) when the fuel was a 5% H2S-95% H-2 mixture at 1273K. Cell performances were stable and showed no significant deterioration during a 48 h period. Impedance measurements showed overall cell resistances decreased with increasing temperature and H2S content of the fuel. The results are promising due to the drastic improvement in sulfur tolerance compared to the current generation of SOFC anode materials. (C) 2004 Elsevier B.V. All rights reserved.