Solid Oxide Electrolysis of H2O and CO2 to Produce Hydrogen and Low-Carbon Fuels

Solid oxide electrolysis cells (SOECs) including the oxygen ion-conducting SOEC (O-SOEC) and the proton-conducting SOEC (H-SOEC) have been actively investigated as next-generation electrolysis technologies that can provide high-energy conversion efficiencies for H2O and CO2 electrolysis to sustainably produce hydrogen and low-carbon fuels, thus providing higher-temperature routes for energy storage and conversion. Current research has also focused on the promotion of SOEC critical components to accelerate wider practical implementation. Based on these investigations, this perspective will summarize the most recent progress in the optimization of electrolysis performance and long-term stability of SOECs, with an emphasis on material developments, technological approaches and improving strategies, such as nano-composing, surface/interface engineering, doping and in situ exsolution. Existing technical challenges are also analyzed, and future research directions are proposed to achieve SOEC technical maturity and economic feasibility for diverse conversion applications.Graphical AbstractSolid oxide electrolysis cells (SOECs), including oxygen ion-conducting SOEC (O-SOEC) and proton-conducting SOEC (H-SOEC), have been actively investigated as one type of next generation electrolysis technologies with high-energy conversion efficiencies, which provide higher-temperature routes for energy storage and conversion.