Perovskite Materials for Solid Oxide Fuel Cell Cathodes

An improved LSCF 6428 perovskite material of the type La12zSrx+zCo0.2+aFe0.8+bO3−δ wherein x=0.4, z=(0.01−0.1), a=(0.01−0.04), and b=(0.05−0.15) for use as an SOFC cathode having increased electronic and ionic conductivity. The general formula is similar to the prior art formulae (La0.6Sr0.4)1−z Co0.2 Fe0.8O3−δ and La0.6Sr0.4 Co0.2 Fe0.8O3−δ but applies the z term to La and Sr independently as well as reducing the overall content of La. Further, by adding a small amount (a) of extra Co ions, catalytic activity, conductivity, and sinterability are further enhanced. Adding small amounts (b) of Fe and/or Fe and Co moderates the thermal expansion coefficient with no adverse effect on crystal structure or fuel cell performance. Improved sinterability, microstructure, and reduced film cracking result in high power density of fuel cells. An inherently low-cost solid state reaction method is described.