Significantly Improving the Durability of Single-Chamber Solid Oxide Fuel Cells: A Highly Active CO₂-Resistant Perovskite Cathode

The single-chamber solid oxide fuel cell (SC-SOFC) represents an attractive alternative to batteries for micropower applications given its simplified stack design, easy gas management, lower operation temperature, and quicker start-up. Its stable operation over long duration relies on the availability of CO₂-resistant cathode materials with high oxygen reduction reaction (ORR) activity. Here, we reported a novel perovskite oxide cathode SrSc_0.075Ta_0.025Fe_0.9O_3-δ (SSTF75), which provides CO₂ resistance and high ORR activity. A peak power density of 1430 mW cm^-2 was achieved with the SSTF75/Sm_0.2Ce_0.8O_1.9 cathode at 650 °C with a methane and oxygen gas mixture (1:1 v/v ratio). It retained stable voltage performance at 600 °C for an over 90 h duration when discharged at a current density of 1000 mA cm^-2. This work not only represents an advancing step in the SC-SOFC field but also authenticates an effective codoping strategy for the design of a CO₂-resistant cathode for low-temperature applications.