中文摘要：

应用丝网印刷和共烧结制备LaNi0.6Fe0.4O3-δ（LNF）-Gd0.2Ce0.8O2（GDC）梯度复合阴极／Gd02Cen802／Sc0.lZro.9Ol.95（ScSZ）／Gdo0.2Ce0.8O2／LaNi0.6Fe0.4O3-δ（LNF）一G如Ce。80：（GDC），组成梯度复合阴极对称电池．实验表明，在750oC工作温度下单层70％LNF一30％GDC（文中均指质量百分比）复合阴极的极化电阻为0．581Q·cm2．而三层60％LNF一40％GDC／70％LNF-30％GDc／100％LNF复合阴极的极化电阻最小（0．452Q·cm^2）．由于阴极组成在ScSZ电解质和LNF阴极之间呈梯度变化，因此获得了最佳的阴极／电解质界面，大大加快了三相界面或气4＊／阴极／电解质三相接触点反应区的扩散，其电荷传递电阻R。和浓差极化电阻吼均减小，因而具有最低的阴极极化电阻值．

英文摘要：

A LNF-GDC composite cathode with a gradual change in the composition between ScSZ electrolyte and LNF cathode was fabricated to reduce the cathode polarization resistance （Rp）. The gradual change in composition between ScSZ electrolyte and LNF cathode shows the decreases in the charge transfer resistance （R~） and gas phase diffusion resistance （Rd）. The results revealed that the Rp value, measuring 0.452 1~ .cm2 at 750 ~C, was the lowest for LNF-GDC composite cathodes with three layers and gradient changes in composition between ScSZ and LNF （Cathode C）, whereas the Rp value of 70%LNF-30%GDC composite cathodes with one layer （Cathode A） was 0.581 l）.cm2. The reduction in Rp for the LNF-GDC composite cathodes with three layers and gradient changes in composition between ScSZ and LNF may be related to the fact that the microstructure of the cathode/electrolyte interfaces is significantly improved, resulting in the increase in the area of triple phase boundaries （TPBs）, which enhanced the surface exchange of oxygen. This implied that the gradient LNF-GDC composite cathodes showed excellent performance in terms of its electrochemical properties.