Perovskite-type (ABO(3)) complex oxides of Sm1-xSrxFe0.7Cr0.3O3-delta (x = 0.5-0.7) series were prepared by a glycine-nitrate combustion process. The crystal structure, oxygen nonstoichiometry, electrical conducting, thermal expansion, and electrocatalytic properties of Sm1-xSrxFe0.7Cr0.3O3-delta perovskites were inspected in view of their use as cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs). Changing the content of Sm3+ at the A-site was demonstrated to be effective in tuning the structure and properties. The variation of the various properties with Sm3+ content was explained in relation to the corresponding evolution of the crystal structure and oxygen nonstoichiometry. Sm0.3Sr0.7Fe0.7Cr0.3O3-delta (x = 0.7) was determined to be the optimal composition in the Sm1-xSrxFe0.7Cr0.3O3-delta series based on a trade-off between the thermal expansion and electrocatalytic properties. Sm0.3Sr0.7Fe0.7Cr0.3O3-delta ceramic specimen exhibited an electrical conductivity of approximately 40 S center dot cm(-1) at 800 degrees C and a thermal expansion coefficient of 14.1 x 10(-6) K-1 averaged in the temperature range from 40 degrees C to 1000 degrees C. At 800 degrees C in air, Sm0.3Sr0.7Fe0.7Cr0.3O3-delta electrode showed a cathodic polarization resistance of 0.19 omega center dot cm(2), a cathodic overpotential of 30 mV at current density of 200 mA center dot cm(-2), and an exchange current density of 257 mA center dot cm(-2). It is suggested that Sm0.3Sr0.7Fe0.7Cr0.3O3-delta is a potential candidate material for cathode of IT-SOFCs in light of its overall properties.