The development of cathode with high oxygen reduction reaction (ORR) activity is crucial for intermediate-temperature solid oxide fuel cells (IT-SOFCs). SrCoO_3-δ oxides, a mixed ion-electron conductivity (MIEC), are promising cathode materials. However, pure SrCoO_3-δ exhibits a hexagonal or rhombohedral structure with poor electrical properties, limiting its application in IT-SOFCs. In this work, high-valence Ce⁴⁺ is doped at the A-site of SrCoO_3-δ perovskite to improve the phase structural stability and electrochemical activity of SrCoO_3-δ. The findings reveal that Ce⁴⁺ doping in small amounts significantly advances the conductivity and ORR activity due to enhanced structural stability. Among the series of samples, Sr_0.95Ce_0.05Co_3-δ (SCC005) presents the best electrochemical performance. Moreover, the addition of Ce_0.8Gd_0.2O_2-δ (GDC) further reduces polarization resistance by about ∼7 times. The peak power density of 1.3 W cm⁻² is obtained at 750 °C for the SCC05-30%GDC cathode. The results indicate that A-site Ce doping is a promising strategy to enhance the ORR activity of SrCoO_3-δ oxides.

开发具有高氧还原反应（ORR）活性的阴极对于中温固体氧化物燃料电池（IT-SOFC）至关重要。 SrCoO _3-δ 氧化物具有混合离子电子电导率（MIEC），是有前途的阴极材料。然而，纯SrCoO _3-δ 呈现六方或菱形结构，电性能较差，限制了其在IT-SOFC中的应用。本工作通过在SrCoO _3-δ 钙钛矿的A位掺杂高价Ce ⁴⁺ 来提高SrCoO _3-δ 的相结构稳定性和电化学活性。研究结果表明，少量的 Ce ⁴⁺ 掺杂由于增强的结构稳定性而显着提高了电导率和 ORR 活性。在该系列样品中，Sr _0.95 Ce _0.05 Co _3-δ （SCC005）呈现出最好的电化学性能。此外，添加Ce _0.8 Gd _0.2 O _2-δ (GDC)进一步将极化电阻降低约~7倍。 SCC05-30%GDC 阴极在 750 °C 时获得 1.3 W cm ⁻² 的峰值功率密度。结果表明，A 位 Ce 掺杂是增强 SrCoO _3-δ 氧化物 ORR 活性的一种有前景的策略。