Sr-doped BaZr0.5Fe0.5O3-δ cathode with improved chemical stability and higher performance for proton-conducting solid oxide fuel cells

A new Ba0.5Sr0.5Zr0.5Fe0.5O3-delta (BSZF) material was proposed as a cathode for proton-conducting solid oxide fuel cells (H-SOFCs). Compared with the traditional Fe-doped BaZrO3 (BZF) cathode, the incorporation of Sr into the lattice decreased the lattice volume of the material but enhanced the chemical stability against CO2 that has been confirmed by both experiments and first-principles calculations. In addition, doping Sr allowed larger oxygen vacancy content and enhanced interaction with O2, facilitating the oxygen reduction reaction. The fuel cell with the BSZF showed an encouraging performance of 1048 mW cm-2 at 700 degrees C, much larger than that of the traditional BZF cell. The analysis for cell resistances revealed that the Sr-doping strategy reduced the cell po-larization resistance, and the reduction was more profound under the loading condition, providing an interesting strategy for designing H-SOFC cathodes.

Automated summary

A new BSZF material was proposed as a cathode for proton-conducting SOFCs. The incorporation of Sr into the lattice improved the chemical stability and enhanced the oxygen vacancy content, leading to improved performance of the fuel cell.