LSCF

LSCF, short for lanthanum strontium cobalt ferrite, is a doped perovskite oxide widely used as a cathode material in solid oxide fuel cells (SOFCs) and related electrochemical devices. Its general formula is La1−xSrx(Co1−yFe y)O3−δ, with common IT-SOFC compositions such as La0.6Sr0.4Co0.2Fe0.8O3−δ. The material combines lanthanum at the A-site with partial substitution by strontium, and a mixed B-site of cobalt and iron. The δ denotes oxygen nonstoichiometry that varies with temperature and oxygen partial pressure, contributing to the material’s mixed ionic and electronic conductivity.

LSCF is classified as a mixed ionic-electronic conductor (MIEC). It exhibits relatively high electronic conductivity and catalytic activity for the oxygen reduction reaction, enabling efficient cathode performance at intermediate temperatures (roughly 600–800 C). Its perovskite structure supports rapid surface exchange and bulk transport of oxygen species, which is advantageous for IT-SOFC operation. The material can be processed into porous cathode structures and used in combinations with various electrolytes, including YSZ and ceria-based systems.

Challenges include surface segregation of strontium under certain high-temperature and reducing conditions, which can degrade electrochemical activity and stability. Interactions with electrolytes at interfaces may cause phase reactions or mechanical stress, and long-term redox and moisture sensitivity can impact durability. To address these issues, researchers explore strategies such as coating or buffering layers (for example, ceria-based materials), optimized A- and B-site doping, and nano-structured or infiltrated cathodes to enhance stability and performance.

LSCF remains a widely studied and deployed cathode option for IT-SOFCs and related electrochemical devices due to its balance of conductivity, activity, and compatibility.