Carbon dioxide (CO₂) emissions have increased since the industrial revolution, contributing to the serious greenhouse effect and global warming. To minimize these effects, many of efforts have been devoted to converting CO₂ into useful chemicals such as carbon monoxide (CO), methane, methanol, and dimethyl ether by using excess electrical energy of sustainable, renewable, and alternative energy sources. Among various technologies for CO₂ conversion including: thermocatalytic, electrochemical, and photochemical reductions,  the electrochemical reaction has a better possibility than the others because the electrochemical reaction is controllable and can utilize alternative energy sources for CO₂ conversion, potentially achieving a carbon-neutral energy cycle.

Several technologies have been studied to reduce CO₂ electrochemically. Due to the advantages of high energy efficiency, good stability, and high faradaic efficiency, solid oxide electrolysis cells (SOECs) are more promising for practical applications in the future than other electrochemical devices. One challenge is to develop a high-performance CO₂ conversion electrode, which should possess high catalytic activity, electronic and ionic conductivity, chemical stability in the CO₂ atmosphere, and good resistivity against carbon deposition. Cermet (e.g., Ni-electrolyte ceramic) has been utilized as a traditional CO₂ conversion electrode for SOECs because Ni metal serves as not only the electrocatalyst but also the electronic conductor. However, the cermet has issues with CO₂ electrolysis due to the oxidation of Ni metal and carbon coking when exposed to a pure or concentrated CO₂ atmosphere. Therefore, mixed ionic-electronic conducting (MIEC) perovskites have been investigated as the potential electrolyte materials for CO₂ electrolysis because perovskites have been considered attractive catalytic materials in the fields of solid oxide fuel cells due to their acceptable electrical conductivity and coking resistance. However, these perovskites have shown relatively low catalytic activity compared to cermet.