The proper-ties and performance of Ba0.5Sr0.5Co0.8Fe0.2O3-delta (PSCF)+Sm0.2Ce0.8O1.9 (SDC) (70:30 in weight ratio) composite cathode for intermediate-temperature solid-oxide fuel cells were investigated. Mechanical mixing of BSCF with SDC resulted in the adhesion of fine SDC particles to the surface of coarse BSCF grains. XRD, SEM-EDX and O-2-TPD results demonstrated that the phase reaction between BSCF and SDC was negligible, constricted only at the BSCF and SDC interface, and throughout the entire cathode with the formation of new (Ba,Sr,Sm,Ce)(Co,Fe)O3-delta perovskite phase at a firing temperature of 900, 1000, and >= 1050 degrees C, respectively. The BSCF + SDC electrode sintered at 1000 degrees C showed an area specific resistance of similar to 0.064 Omega cm(2) at 600 degrees C, which is a slight improvement over the BSCF (0.099 Omega cm(2)) owing to the enlarged cathode surface area contributed from the fine SDC particles. A peak power density of 1050 and similar to 382 mW cm(-2) was reached at 600 and 500 degrees C, respectively, for a thin-film electrolyte cell with the BSCF + SDC cathode fired from 1000 degrees C. (c) 2008 Elsevier B.V. All rights reserved.