Long-term stability of perovskite cathodes in solid oxide fuel cells
Solid oxide fuel cells (SOFCs) are the cleanest and most efficient energy technology for direct conversion to electricity of a wide variety of fuels. In addition to the efforts to reduce the operating temperature of SOFCs from 1000°C to below 800°C, research studies on the underlying degradation mechanisms are envisioned to improve the long-term stability and durability of the components of SOFCs. In general, the SOFC is comprised of a porous cathode, dense electrolyte, porous anode, interconnects and current collectors. The cathode is a critical component in SOFCs since it displays cell polarization resistance which reduction makes an important challenged to be addressed. The deactivation of the cathode often caused by the: 1) formation of interfacial products in the vicinity of the electrolyte and the 2) surface precipitation from the reaction of the components of the cathode with the air/fuel or interconnects impurities such as sulfur and chrome. In this presentation, an attempt is made to highlight the influence of interfacial reaction products at the cathode-electrolyte interface on the long-term stability of cathodes and effect of the cathode composition on its reactivity with the sulfur contamination in the air.