疏松多孔Ce0.9Gd0.1O1.95电解质骨架对GdBa0.7Sr0.3Co2O5+δ阴极材料性能的影响

Effect of Porous Ce0.9Gd0.1O1.95Electrolyte Skeleton on Properties of Cathode Material GdBa0.7Sr0.3Co2O5+δ

采用EDTA-柠檬酸盐改进的溶胶凝胶法成功制备出用于中温固体氧化物燃料电池(IT-SOFCs)的阴极材料GdBa0.7Sr0.3Co2O5+δ(GBSCO)和电解质材料Ce0.9Gd0.1O1.95(GDC),使用X射线衍射仪(XRD)和扫描电子显微镜(SEM)表征了材料的晶体结构和微观结构特性。采用电化学交流阻抗谱(EIS)和线性扫描伏安法(LSV),对组装的对称半电池三电极体系的电化学性能进行了表征。实验结果表明:随着测试温度的升高,两种不同结构半电池的电化学性能均有明显提升。当测试温度为750℃时,半电池GBSCO//GDC的面积比界面电阻为0.166Ω·cm^2,极化电流密度为0.370A·cm-2;相同温度下,半电池GBSCO//多孔GDC骨架/GDC的面积比界面电阻为0.118Ω·cm^2,极化电流密度为0.763A·cm-2;后者的面积比界面电阻要比前者低0.048Ω·cm^2,而极化电流密度要比前者高0.393A·cm-2。体现了GBSCO//多孔GDC骨架/GDC结构的优异性。

In this work,the cathode material GdBa0.7Sr0.3Co2O5+δ(GBSCO)and electrolyte material Ce0.9Gd0.1O1.95(GDC)for intermediate-temperature solid oxide fuel cells(IT-SOFCs)have been synthesized via EDTA-citrateprocess.The crystal structure and microstructure characteristics of the materials were characterized by X-ray diffraction(XRD)and scanning electron microscopy(SEM).The electrochemical performances were measured with three-electrode method.Electrochemical impedance spectroscopy(EIS)and linear sweep vol tammetry(LSV)of the half-cell were carried out with CHI660Delectrochemical analyzer.The experimental results show that the area specific resistance of the half-cell GBSCO//GDC is 0.166Ω·cm^2,and the polarization current density is 0.370A·cm-2 at 750℃.At the same temperature,the area specific resistance of the half-cell GBSCO//porous GDC skeleton/GDC is 0.118Ω·cm^2,and the polarization current density is 0.763A·cm-2.It was clear that the former was substantially higher than those of another half-cell.It reflects the superiority of GBSCO//porous GDC skeleton/GDC structure.