High-performance BaCo0.5Fe0.5O3-δ-Pr6O11 heterostructure in proton conductor solid oxide fuel cells

The cathode is a critical component of proton-conducting fuel cells (H-SOFCs), as its performance is influenced by the distinct atmospheric conditions on the cathode side. In this study, Pr 6 O 11 was incorporated into the BaCo 0.5 Fe 0.5 O 3-δ cathode material to form BaCo 0.5 Fe 0.5 O 3-δ -Pr 6 O 11 heterostructured composites. These heterostructures significantly enhance oxygen ion diffusion and valence electron transitions, leading to improved electrical conductivity and electrocatalytic activity in H-SOFCs. XPS analysis demonstrated that the BaCo 0.5 Fe 0.5 O 3-δ -Pr 6 O 11 cathode exhibits superior chemical stability and oxygen adsorption capacity. Symmetric cell tests revealed that its polarization impedance is significantly lower than that of single-phase BaCo 0.5 Fe 0.5 O 3-δ , indicating excellent ORR activity. Furthermore, an H-SOFC with a BaCo 0.5 Fe 0.5 O 3-δ -Pr 6 O 11 cathode achieved a peak power density of 847 mW cm −2 at 700 °C, markedly outperforming the single-phase cathode.