Enhancing performance of proton ceramic fuel cells through fluorine-doped perovskite oxides

Proton ceramic fuel cell efficiently converts chemical energy into electrical energy, representing a pivotal component of future energy systems. However, its current performance is hindered by limitations in cathode and electrolyte materials, thereby impeding commercialization. Anion doping emerges as a promising strategy to enhance the electrochemical efficiency of perovskite-based cathodes and electrolytes. However, integrating this approach within a single-cell structure still requires further research. In this study, F-doped perovskite oxides BaCo_0.4Fe_0.4Zr_0.1Y_0.1O_2.9-δF_0.1 (BCFZYF) and BaZr_0.1Ce_0.7Y_0.1Yb_0.1O_2.9-δF_0.1 (BZCYYbF) were synthesized for use as the cathode and electrolyte, respectively, in proton ceramic fuel cells. Our findings demonstrate that F-doped perovskite oxides exhibit superior electrochemical performance and enhanced structural stability. Furthermore, doping both electrodes and electrolytes with F ions improves their interfacial compatibility. The cell configuration BCFZYF | BZCYYbF | Ni-BZCYYbF achieved a peak power density of 998 mW·cm⁻² at 650 °C using H₂ as fuel, and it maintained stable operation for over 400 h at 550 °C with a current density of 400 mA·cm⁻². This research underscores an effective strategy for enhancing the performance and durability of proton ceramic fuel cells.