【摘要】 采用溶胶-凝胶法制备了La_0.7Sr_0.3Co_1-xFe_xNi_0.1O_3-δ（x=0.3～0.6）系列阴极粉体。使用扫描电镜（SEM）观察了粉体形貌，并采用X射线衍射（XRD）和热膨胀仪对其物相结构及热膨胀性能进行探究，发现随着Fe元素掺杂量的增加，晶体结构未发生变化且热膨胀系数下降。进一步对材料进行了电导率测试以及电化学阻抗谱测试。结果表明当Fe的掺杂量为0.4时，电导率达到峰值，400℃时为332.71 S/cm。此外，La_0.7Sr_0.3Co_0.5-Fe_0.4Ni_0.1O_3-δ的电化学阻抗谱表明在800℃时，极化电阻为0.55Ωcm²,具有成为IT-SOFC阴极材料的潜力。更多还原

【Abstract】 La_0.7Sr_0.3Co_1-xFe_xNi_0.1O_3-δ（x=0.3-0.6） series cathode powders are prepared by sol-gel method. The morphology of the powder is respected by scanning electron microscope（SEM）. The phase structure and thermal expansion property of the powder are examined by X-ray diffraction（XRD） and thermal dilatometer, respectively. It is noted that the crystal structure does not change and the thermal expansion coefficient decreases with the increase of Fe doping content. Furthermore, the electrical conductivity and electrochemical impedance spectroscopy of the materials are tested. The results show that the conductivity reaches the peak when the doping amount of Fe is 0.4, and the conductivity is 332.71 S/cm at 400 ℃. In addition, the electrochemical impedance spectra of La_0.7Sr_{0. 3}Co_0.5Fe_0.4Ni_0.1O_3-δ is shown that the area specific resistance of La_0.7Sr_{0. 3}Co_0.5Fe_0.4Ni_0.1-O_3-δ is 0.55 Ω cm² at 800 ℃, which shows that it has the potential to be used as a cathode material for IT-SOFC.更多还原