Abstract Perovskite oxides of composition La1−xSrxFe0.7Ni0.3O3−δ (LSFN-x, 0 ≤ x ≤ 0.4) were evaluated as candidate cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs). Their crystal structures, electrical conductivity, thermal expansion coefficient (TEC), and electrochemical performance were investigated as a function of their Sr content. An orthorhombic structure was obtained when 0.3 equivalents of Ni were substituted at the Fe sites, resulting in LaFe0.7Ni0.3O3−δ, and the crystal structure was transformed from orthorhombic to hexagonal upon the substitution of Sr at La sites. Sr doping was found to increase the TEC of the LSFN material, resulting in a good thermal match with the commonly used Gd0.1Ce0.9O2−δ (GDC) electrolyte. The LSFN-0.2 also exhibited good chemical compatibility with the GDC electrolyte at temperatures

中文翻译：

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用于中温 SOFC 的 La1−Sr Fe0.7Ni0.3O3− 阴极的热膨胀和电化学性能提高

摘要 组成为 La1-xSrxFe0.7Ni0.3O3-δ (LSFN-x, 0 ≤ x ≤ 0.4) 的钙钛矿氧化物被评估为中温固体氧化物燃料电池 (IT-SOFC) 的候选阴极材料。研究了它们的晶体结构、电导率、热膨胀系数 (TEC) 和电化学性能与 Sr 含量的关系。当 0.3 当量的 Ni 在 Fe 位点被取代时，获得了正交结构，导致 LaFe0.7Ni0.3O3-δ，并且在 La 位点取代 Sr 后，晶体结构从正交晶格转变为六方晶系。发现 Sr 掺杂会增加 LSFN 材料的 TEC，从而与常用的 Gd0.1Ce0.9O2-δ (GDC) 电解质具有良好的热匹配。LSFN-0。