Developing highly active and robust cathodes remains challenging for solid oxide fuel cells (SOFCs). Therefore, we report an A-site medium-entropy double perovskite oxide PrBaSrCaCeCoO (PBSCCC) and its electrocatalytic activity and CO tolerance property are systematically probed. The PBSCCC cathode exhibits excellent oxygen reduction reaction (ORR) activity with a low polarization resistance of 0.027 Ω cm at 700 °C. More importantly, compared to PrBaCoO (PBC) and PrBaCaCoO (PBCC) oxides, its CO resistance is prominently enhanced with significantly less BaCO and CoO impurities formed. The superior ORR performance and structure stability are mainly attributed to its high electrical conductivity and significantly reduced surface cation segregations. Our results show that the potential of PBSCCC as a cathode material for SOFCs is enormous and also prove the rationality and feasibility of entropy engineering for cathode development.

中文翻译：

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一种中熵设计的双钙钛矿氧化物，用于固体氧化物燃料电池的高效且耐二氧化碳的阴极

对于固体氧化物燃料电池（SOFC）来说，开发高活性且坚固的阴极仍然具有挑战性。因此，我们报道了一种A位中熵双钙钛矿氧化物PrBaSrCaCeCoO（PBSCCC），并系统地探讨了其电催化活性和CO耐受性。 PBSCCC 阴极表现出优异的氧还原反应 (ORR) 活性，在 700 °C 时具有 0.027 Ω cm 的低极化电阻。更重要的是，与 PrBaCoO (PBC) 和 PrBaCaCoO (PBCC) 氧化物相比，其耐 CO 性能显着增强，并且形成的 BaCO 和 CoO 杂质显着减少。优异的ORR性能和结构稳定性主要归因于其高电导率和显着减少的表面阳离子偏析。我们的结果表明PBSCCC作为SOFC阴极材料的潜力是巨大的，也证明了熵工程用于阴极开发的合理性和可行性。