Developing a new low-cost and high-performance oxygen reduction electrode has been an imperative assignment for the development of intermediate temperature solid oxide fuel cells (IT-SOFCs). Herein, a new family of SrCo_0.9−xNb_0.1Ni_xO_3−δ (SCNN, 0.1 ≤ x ≤ 0.3) perovskites have been developed as a promising cathode for IT-SOFCs with improved cathode attributes with respect to their parent compound, SrCo_0.9Nb_0.1O_3−δ (SCN). Partial Ni substitution enhanced the oxygen reduction reaction (ORR) activity for SrCo_0.9−xNb_0.1Ni_xO_3−δ. The SrCo_0.7Nb_0.1Ni_0.2O_3−δ (SCNN2) cathode exhibited a polarization resistance of 0.066 Ω cm² at 700 °C in air, 44% lower than that of SCN. The remarkable ORR catalytic activity for SrCo_0.9−xNb_0.1Ni_xO_3−δ could be ascribed to the improved oxygen bulk diffusion and surface exchange coefficient arising from the introduction of oxygen vacancies with Ni doping according to electrical conductivity relaxation (ECR) and thermogravimetric analysis (TGA) results. Furthermore, the SCNN2 cathode demonstrated excellent stability in air and high CO₂ tolerance and recovery performance, demonstrating that the SCNN2 perovskite can be a very promising cathode for application in IT-SOFCs and other energy transformation systems.

中文翻译：

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高活性且稳定的阴极，可用于中温固体氧化物燃料电池中的氧还原

开发新型低成本，高性能的氧还原电极已成为开发中温固体氧化物燃料电池（IT-SOFC）的当务之急。在此，的SrCO的一个新的家庭_{0.9- X}的Nb _0.1的Ni _X ø _{3- δ}（SCNN，0.1≤ X ≤0.3）的钙钛矿已经被开发作为用于IT-SOFC的一个有前途的阴极与改进的阴极相对于它们的母体化合物属性， SrCo _0.9 Nb _0.1 O _{3− δ}（SCN）。部分的Ni取代增强了氧还原反应（ORR）活性的SrCO _{0.9- X}的Nb _0.1的Ni _XO _{3- δ}。SrCo _0.7 Nb _0.1 Ni _0.2 O _{3− δ}（SCNN2）阴极在700°C的空气中显示出0.066Ωcm ²的极化电阻，比SCN低44％。对的SrCO显着的ORR催化剂活性_{0.9- X}的Nb _0.1的Ni _X ö _{3- δ}可以归因于根据电导率弛豫（ECR）和热重分析（TGA）结果，通过掺入Ni掺杂的氧空位而提高了氧的体积扩散和表面交换系数。此外，SCNN2阴极在空气中表现出出色的稳定性，并具有很高的CO ₂耐受性和恢复性能，这表明SCNN2钙钛矿可以成为IT-SOFC和其他能源转换系统中非常有希望的阴极。