A cobalt-free cubic perovskite oxide Sm(0.5)Sr(0.5)Fe(0.8)Cu(0.2)O(3-delta) (SSFCu) was investigated as a novel cathode for intermediate temperature solid oxide fuel cells (IT-SOFCs). The thermal expansion coefficient (TEC) of SSFCu was close to that of Sm(0.2)Ce(0.8)O(1.9)(SDC) electrolyte and the electrical conductivity of SSFCu sample reached 72-82 S cm(-1) in the commonly operated temperatures of IT-SOFCs (400-600 degrees C). Symmetrical electrochemical cell with the configuration of SSFCu/SDC/SSFCu was applied for the impedance study and area specific resistance (ASR) of SSFCu cathode material was as low as 0.085 Omega cm(2) at 700 degrees C. Laboratory-sized tri-layer cells of NiO-SDC/SDC/SSFCu were operated from 450 to 700 degrees C with humidified hydrogen (similar to 3% H(2)O) as fuel and the static air as oxidant. A maximum power density of 808 mW cm(2) was obtained at 700 degrees C for the single cell. (C) 2010 Published by Elsevier Ltd on behalf of Professor T. Nejat Veziroglu.