In this paper, the partial substitution of atomic elements from the A site of a perovskite is investigated in order to develop cathode materials for solid oxide fuel cell (SOFC) applications. Herein, Sr2-xCaxFe1.5Mo0.5O6-delta (SCFM), compounds were investigated by characterizing structural properties, chemical compatibility, electrical properties, electrochemical performance and stability. Thermal expansion coefficients were found to decrease when increasing the Ca content. X-ray photoelectron spectroscopy analysis suggests that Ca doping significantly affects the Fe2+/Fe3+ and Mo6+/Mo5+ ratios. For a doping level of x = 0.4, the sample showed the lowest interface polarization (R-p), the highest conductivity and a maximum power density of 1.26 W cm(-2) at 800 degrees C. These results suggest that SCFM cathode materials are excellent candidates for intermediate temperature solid oxide fuel cells applications. (C) 2016 Elsevier B.V. All rights reserved.