Thiam Leng Chew, VS Prasadarao Lingam
This study reviews the perovskite cathode materials for solid oxide fuel cells (SOFCs), focusing on their types, structures, synthesis, coating methods, and challenges. Manganese-based cathodes commonly offer good stability and high-temperature oxygen reduction reaction (ORR) activity. Cobalt-based cathodes provide excellent conductivity, though high thermal expansion and reactivity pose issues. Ferrite-based cathodes are cost-effective and stable but have limited oxygen vacancies. There are different types of perovskite structures including 3D, layered, and Ruddlesden–Popper types, each with unique electrochemical benefits. Commonly, perovskite materials could be synthesized via different methods, which include co-precipitation, solid-state reactions, hydrothermal, Pechini, and sol-gel techniques influence material quality. On the other hand, coating techniques such as dip coating, spin coating, screen printing coating, tape casting coating and brush coating are commonly applied for coating perovskite cathode layer on SOFC. Despite numbers of reported studies relevant to perovskite cathode materials for SOFC, several challenges remain which include chemical degradations, delamination and etc. It is recommended that future efforts focus on addressing these challenges.