Self-assembled co-free Fe-based perovskite oxygen electrode for intermediate temperature solid oxide fuel cells

The cathode material is a key determinant in the advancement of solid oxide fuel cells (SOFCs). However, achieving a balance between high electrocatalytic activity and long-term stability is still a major challenge. In this work, an in situ self-assembly strategy was developed to fabricate Pr 0.4 Sr 0.5 Ce 0.1 Fe 0.8 Ni 0.2 O 3-δ (PSCFNX) composite materials. During the calcination process, CeO 2 and NiO secondary phases spontaneously segregate and grow on the surface of the Pr 0.4 Sr 0.5 Ce 0.1 Fe 0.8 Ni 0.2 O 3-δ (PSCFN) phase. This process leads to the formation of intimate three-phase junctions and abundant bonded heterointerfaces, thereby expanding the electrochemically active area and significantly enhancing catalytic performance. The optimized PSCFNX material exhibits a low area-specific resistance of 0.081 Ω cm 2 at 800 °C. Correspondingly, the cell with an optimized cathode achieves a high peak power density of 1.576 W cm −2 at 800 °C and exhibits a long-term stability exceeding 100 h. This study confirms that the Pr 0.4 Sr 0.5 Ce 0.1 Fe 0.8 Ni 0.2 O 3-δ materials could enhance SOFC performance.