The SrCo0.9Sb0.1O3-delta (SCS) composite oxide with cubic perovskite structure was synthesized by a modified Pechini method and examined as a novel cathode for protonic ceramic membrane fuel cells (PCMFCs). At 700 degrees C and under open-circuit condition, symmetrical SCS cathode on BaZr0.1Ce0.7Y0.2O3-delta (BZCY7) electrolyte showed low polarization resistances (R-p) of 0.22 Omega cm(2) in air. A laboratory-sized tri-layer cell of NiO-BZCY7/BZCY7/SCS was operated from 500 to 700 degrees C with humidified hydrogen (similar to 3% H2O) as fuel and the static air as oxidant. A high open-circuit potential of 1.004V, a maximum power density of 259mWcm(-2), and a low polarization resistance of the electrodes of 0.14 Omega cm(2) was achieved at 700 degrees C. (c) 2008 Elsevier B.V. All rights reserved.