Developing new cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs) is still challenging. In this study, co-doped Sr₃Fe₂O_7-δ Ruddlesden-Popper (R-P) (Sr_3-xPr_xFe_1.8Co_0.2O_7-δ x = (0–0.3)) cathode is synthesized by the polymer complex technique as a cathode for IT-SOFCs. The synthesized powders show a desired tetragonal structure of Sr_3-xPr_xFe_1.8Co_0.2O_7-δ with an I4/mmm space group. The effect of Pr and Co on the physical, thermal, electrical, and electrochemical properties of the cathodes is investigated. The results reveal that Pr/Co co-doping improves electrochemical properties while increasing the electrical resistivity and average thermal expansion coefficients (TECs). To evaluate the long-term thermal stability of the cathode, they are heated at 800 °C for 100 h in the air, and no contaminant is found. In the optimal amount of Pr and Co (Sr_2.7Pr_0.3Fe_1.8Co_0.2O_7-δ), area-specific resistance (ASR) of 0.058 Ω.cm² and maximum output power density of 745 mW/cm² are obtained at 800 °C. Strong oxygen-reducing reaction (ORR) activity and long-term thermal stability make Sr_2.7Pr_0.3Fe_1.8Co_0.2O_7-δ an appropriate alternative cathode material for IT-SOFC.

开发用于中温固体氧化物燃料电池（IT-SOFC）的新型阴极材料仍然具有挑战性。在本研究中，共掺杂Sr ₃ Fe ₂ O _7-δ Ruddlesden-Popper (RP) (Sr _3-x Pr _x Fe _1.8 Co _0.2 O _7-δ x = (0–0.3)) 阴极由聚合物合成复杂的技术作为 IT-SOFC 的阴极。合成的粉末显示出具有I4/mmm空间群的Sr _3-x Pr _x Fe _1.8 Co _0.2 O _7-δ所需的四方结构。研究了 Pr 和 Co 对阴极物理、热、电和电化学性能的影响。结果表明，Pr/Co 共掺杂改善了电化学性能，同时增加了电阻率和平均热膨胀系数 (TEC)。为了评估阴极的长期热稳定性，将它们在空气中在800℃下加热100小时，没有发现污染物。在Pr和Co的最佳用量（Sr _2.7 Pr _0.3 Fe _1.8 Co _0.2 O _7-δ ）下，获得了0.058 Ω.cm ²的面积比电阻（ASR）和745 mW/cm ²的最大输出功率密度。800℃。强氧还原反应（ORR）活性和长期热稳定性使Sr _2.7 Pr _0.3 Fe _1.8 Co _0.2 O _7-δ成为IT-SOFC的合适替代阴极材料。