In this work, fundamental material properties of compounds in the system (La,Pr)₂(Ni,Co)O_4+δ as well as their performance as air electrodes in solid oxide electrolysis cells were investigated. Nickelates co-doped with Pr and Co were characterized on a material basis by means of X-ray diffraction and thermogravimetry. Conductivity and conductivity relaxation measurements were performed in order to obtain the electronic conductivity as well as the chemical surface exchange coefficient and the chemical diffusion coefficient of oxygen as a function of temperature and oxygen partial pressure. These parameters can be regarded as the most essential properties at the material level required to assess the suitability of mixed ionic-electronic conducting ceramics for application as air electrode in solid oxide cells. The electrode performance of the materials was then tested on fuel electrode-supported button cells at 800°C. The electrodes were applied by screen-printing and the effect of varying the Pr-content and Co-content of the electrode powder was investigated. Cell tests were performed by means of current-voltage measurements in electrolysis mode. While no significant impact of Pr-doping on the investigated material properties was observed, the electrode performance of Pr-containing materials was significantly better than for the Pr-free compound, which has been discussed in detail.

中文翻译：

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稀土镍酸盐中的 Pr 和 Co 取代：作为 SOEC 空气电极的应用

_{在这项工作中，研究了(La,Pr) 2} (Ni,Co)O _4+δ系统中化合物的基本材料性质以及它们在固体氧化物电解池中作为空气电极的性能。通过 X 射线衍射和热重分析对共掺杂 Pr 和 Co 的镍酸盐进行了材料表征。进行电导率和电导率弛豫测量以获得电子电导率以及氧的化学表面交换系数和化学扩散系数作为温度和氧分压的函数。这些参数可以被视为评估混合离子电子导电陶瓷作为固体氧化物电池中的空气电极的适用性所需的材料水平上最基本的特性。然后在 800°C 的燃料电极支持的纽扣电池上测试材料的电极性能。通过丝网印刷来施加电极，并研究了改变电极粉末的Pr含量和Co含量的影响。电池测试是通过电解模式下的电流-电压测量来进行的。虽然没有观察到 Pr 掺杂对所研究的材料性能产生显着影响，但含 Pr 材料的电极性能明显优于不含 Pr 的化合物，对此进行了详细讨论。