应用丝网印刷和共烧结制备LaNi_0.6Fe_0.4O_3-δ(LNF)-Gd_0.2Ce_0.8O₂(GDC)梯度复合阴极/Gd_0.2Ce_0.8O₂/Sc_0.1Zr_0.9O_1.95(ScSZ)/Gd_0.2Ce_0.8O₂/LaNi_0.6Fe_0.4O_3-δ(LNF)-Gd_0.2Ce_0.8O₂(GDC)，组成梯度复合阴极对称电池. 实验表明，在750 ^oC工作温度下单层70%LNF-30%GDC（文中均指质量百分比）复合阴极的极化电阻为0.581 Ω·cm²，而三层60%LNF-40%GDC/70%LNF-30%GDC/100%LNF复合阴极的极化电阻最小（0.452 Ω·cm²）. 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体/阴极/电解质三相接触点反应区的扩散，其电荷传递电阻R_ct和浓差极化电阻R_d均减小，因而具有最低的阴极极化电阻值.

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 (R_p). The gradual change in composition between ScSZ electrolyte and LNF cathode shows the decreases in the charge transfer resistance (R_ct) and gas phase diffusion resistance (R_d). The results revealed that the Rp value, measuring 0.452 Ω·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 Ω·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.