Stainless Steel/Yttria Stabilized Zirconia Composite Supported Solid Oxide Fuel Cell

Abstract

In this paper composite supports for solid oxide fuel cells were fabricated and evaluated. Substrates were composed of stainless steel and yttria stabilized zirconia (YSZ) powders mixed in different volume ratios. Their sintering behavior (linear shrinkage, resulting porosity) and high temperature properties (oxidation resistance, electrical conductivity) were evaluated. Based on those results the best composition for composite supports was selected and fuel cells were fabricated. Thin YSZ electrolytes were deposited on one side of the support and sintered at 1350 °C in pure hydrogen, while LNF (LaNi0.6 Fe0.4 O3 ) cathodes were deposited on the top of the electrolyte and fired in situ at 800 °C. The fuel cells provided power density of about 80 mWcm-2 at 800 °C. It is worth noting that this performance was achieved without adding any catalytically active phases into composite support, while at the same time the supports exhibited relatively low porosity. This demonstrates that stainless steel can serve as an anode active material. Degradation of this fuel cell was fast (12%/h), nonetheless its performance seems interesting for further investigation.