The composite cathode consisting of A-site deficient perosvkite material La0.58Sr0.4Co0.2Fe0.8O3-delta (L58SCF) and Ce0.8Gd0.2O2-delta (GDC) on YSZ electrolyte is studied for potential applications in intermediate/low-temperature solid oxide fuel cells (SOFCs). Impedance spectroscopy measurements are performed in air over the temperature range of 600-800 degrees C under open circuit potential. The results show that the addition of 40 wt.% GDC to L58SCF (L58SCF-GDC40) results in the lower polarization resistance (0.07 ohm cm(2) at 800 degrees C, 0.11 ohm cm(2) at 750 degrees C and 0.22 ohm cm(2) at 700 degrees C than other composite cathodes and its activation energy values calculated for the low- and high-frequency arcs are 0.86 and 1.10 eV, respectively. The composite cathode exhibit high exchange current density and low charge-transfer resistance. (C) 2007 Elsevier B.V. All rights reserved.