Performance and Stability of LaSr₂Fe₂CrO9-δ-Based Solid Oxide Fuel Cell Anodes in Hydrogen and Carbon Monoxide

Composite solid oxide fuel cell (SOFC) anodes consisting of LaSr 2 Fe 2 CrO 3-δ (LSFeCr) and Gd 0.1 Ce 0.9 O 2-δ (GDC) were evaluated during operation on H 2 , H 2 O-Ar-H 2 , CO, and CO-H 2 mixtures. Impedance spectroscopy studies showed three different electrode processes that varied in importance with temperature and fuel composition. The primary impedance response peaked at ∼2 Hz and followed a similar dependence on H 2 partial pressure in both H 2 -H 2 O-Ar and H 2 –CO mixtures. The total anode polarization resistance at 800°C increased by a factor of ∼2 on going from pure H 2 fuel to pure CO.