The AAO-supported thin-film SOFC with a sputtered-SDC/ALD–YSZ/sputtered-SDC sandwich electrolyte shows a high maximum power density of 562 mW cm−2 at 450 °C.

Obtaining a catalyst with high activity and thermal stability is essential for high-performance energy conversion devices operating at an elevated temperature. Herein, the design and fabrication of a heterogeneous catalyst with an ultrathin CeO2 overlayer via atomic layer deposition (ALD) on Pt electrodes for low-temperature solid oxide fuel cells (LT-SOFCs) is reported. The cell with a CeO2-overcoated (five ALD cycles) Pt cathode shows lower activation resistance by 50% after a 10 h operation and higher thermal stability by a factor of 2 compared with the cell with a Pt-only cathode, which is known to be the best single catalyst at 450 °C. Eventually, a thin-film SOFC with a highly active and stable CeO2-overcoated cathode based on an anodized aluminum oxide (AAO) substrate demonstrates a high peak power density of 800 mW cm–2 at 500 °C, which is the highest performance ever reported for an AAO-based SOFC at this temperature.

Low‐temperature solid oxide fuel cells (LT‐SOFCs, operating temperature≤600 °C) are advantageous in potential applicability, affordability, and durability compared to conventional SOFCs (operating temperature: 800–1000 °C). Direct operation of LT‐SOFCs on liquid alcohol fuels can further improve their portability as well as accessibility to the fuel. In this review, we overview the results of LT‐SOFCs directly fueled by liquid alcohols that operate at 600 °C and below. Fundamentals regarding operation principles, losses, as well as reactions associated with liquid alcohol‐fueled LT‐SOFCs are presented. The materials, structures, and fabrication processes of cell components, namely anode, electrolyte, and cathode, are mainly reviewed. The electrochemical performances of alcohol‐fueled LT‐SOFCs are also summarized and compared with those of H2‐fueled LT‐SOFCs.