A critical review of the nano-structured electrodes of solid oxide cells

Renewable energies from solar and wind power are playing an ever increasing role in meeting the tremendous global energy demand with substantially reduced carbon emissions; however, their intermittent nature poses a critical challenge for sustainability and practical applications. The capability of solid oxide cells (SOCs) to operate in both fuel cell and electrolysis modes makes them one of the most important candidates for efficient storage and regeneration of renewable energies. Here we present a critical review and prospects on the development of key fabrication techniques, e.g. wet infiltration, exsolution and direct assembly, for nanostructured electrodes, one of the most critical issues affecting the performance and stability of SOC technologies. The traits and challenges of these techniques are thoroughly discussed, with an aim to provide a critical guide for future design and development of more refined, high-performing nanostructured electrodes for SOCs.