B-site substituted lanthanum strontium ferrites as electrode materials for electrochemical applications

Abstract

Abstract For electrochemical systems such as solid oxide fuel cells (SOFCs) or solid oxide electrolyzer cells (SOECs), perovskites are widely used as cathode material for the reduction of molecular oxygen. At present, strontium-substituted lanthanum manganite, La1-x Sr x MnO3-δ (LSM), is used as standard SOFC cathode material for operation at high temperatures, whereas strontium-substituted lanthanum ferrite (LSF) is alternatively explored for medium-temperature SOFCs. Moreover, LSF is considered to be a potential candidate for oxygen separation membranes as the material reported interesting electrical properties. The design of new perovskite-type La transition-metal oxides is of significant technological importance in order to reduce the operating temperature to 600-800 °C and thus to reduce the SOFC system cost. For investigations on a new material class, (La1-x Sr x ) y Fe1-z (Ni,Cu) z O3-δ was synthesized by a spray-pyrolysis process and modified on the A-site in both stoichiometric and non-stoichiometric configurations and on the B-site by substituting Fe with Ni and Cu.