【摘要】 通过溶胶凝胶法制备了Nb掺杂Nd_0.6Sr_0.4Co_1-xNb_xO_3-δ钙钛矿氧化物，并将其作为阴极材料应用于SOFC领域。通过扫描电镜、X射线衍射及热膨胀仪探究了材料的微观形貌、物相结构以及热膨胀特性。实验结果表明，随着Nb掺杂量的增加，原结构由正交相向立方相转变；热膨胀系数也随之降低。通过电化学工作站对材料进行了电导率、电化学阻抗谱和单电池功率密度测试。测试结果表明Nb含量的增加降低了原结构的电导率。当Nb掺杂量达到0.06时，Nd_0.6Sr_0.4Co_0.94Nb_0.06O_3-δ具有最低的极化电阻，800℃时为0.061Ω·cm²;同时对其进行功率密度测试，在800℃时其功率为167.9 mW/cm²,具有良好的电化学性能，可作为中低温SOFC阴极材料。更多还原

【Abstract】 Nb-doped Nd_0.6Sr_0.4Co_1-xNb_xO_3-δ perovskite oxides are prepared by sol-gel method and used as cathode materials in SOFC field. The microstructure, phase structure and thermal expansion properties of the materials are examined by scanning electron microscope, X-ray diffraction and thermal dilatometer. The experimental results show that the original structure changes from orthorhombic phase to cubic phase and the coefficient of thermal expansion decreases with the increase of Nb doping. The conductivity, electrochemical impedance spectroscopy and power density of a single cell are measured by electrochemical workstation. The test results show that the electrical conductivity of the original structure decreases with the increase of Nb content. When the amount of Nb doping reaches 0.06, Nd_0.6Sr_0.4Co_0.94Nb_0.06O_3-δ has the lowest polarization resistance, which is 0.061 Ω cm² at 800 ℃. Meanwhile, the power density test shows that the power is 167.9 mW/cm² at 800 ℃. It has well electrochemical performance and can be used as a medium and low temperature SOFC cathode material.更多还原