We investigated the performance of Ag/La_0.6Sr_0.4Co_1-xFe_xO₃ (x = 0;0.8) nanotube composite cathodes using samaria-doped ceria as electrolyte. These composites were prepared by mixing a commercial Ag paste and La_0.6Sr_0.4Co_1-xFe_xO₃ (x = 0;0.8) nanotubes synthesized by the pore wetting technique using plastic templates. Electrochemical impedance spectroscopy analyses showed that the incorporation of La_0.6Sr_0.4Co_1-xFe_xO₃ nanotubes significantly enhances the performance of the cathode in comparison to pure Ag due to their high specific surface area.