Advances in sputtering-based thin-film engineering for low-temperature solid oxide fuel cells

The introduction of thin-film architectures in solid oxide fuel cells (SOFCs) has emerged as an effective strategy for lowering operating temperatures by reducing ohmic resistance and increasing the density of electrochemically active sites. Achieving these improvements requires precise control over the composition, thickness, and microstructure of the electrode and electrolyte layers. Among various thin-film deposition techniques, sputtering offers exceptional tunability in film growth, enabling the fabrication of thin-film layers tailored to the specific functional requirements of SOFCs. This review outlines the working principles of sputtering and highlights how deposition parameters govern thin-film growth. Recent advances in sputtered thin-film electrodes and electrolytes are summarized, with a focus on the correlation between nanoscale structural engineering and electrochemical performance. Finally, this review provides insights into the current challenges associated with sputtered SOFC components and discusses how sputtering-driven tuning of film composition and architecture can be leveraged to advance low-temperature SOFCs.