The electrochemical properties of LaBaCo2O5+delta-xSm(0.2)Ce(0.8)O(1.9) (LBCO-xSDC, x = 20, 30, 40, 50, 60, wt%) were investigated for the potential application in intermediate-temperature solid oxide fuel cells (IT-SOFCs). The LBCO-50SDC composite cathode exhibited the best electrochemical performance in the LBCO-xSDC cathodes. With x = 50 wt%, the ASR was 1.308 Omega cm(2) at 500 degrees C(0.267 Omega cm(2) at 600 degrees Cand 0.052 Omega cm(2) at 700 degrees C). The maximum of exchange current density i(0) was 0.5630 A cm(2) at 700 degrees C. The improved electrochemical properties of LBCO-50SDC were ascribed to the porous structures of the cathode and more cathode/electrolyte/gas triple phase boundary (TPB) areas. (C) 2009 Elsevier Ltd. All rights reserved.