The Sr0.75Y0.25Co0.5Mn0.5O3-y (SYCM) oxide with a cubic perovskite structure was examined as a promising cathode material for intermediate temperature solid oxide fuel cells (IT-SOFCs). The electrical conductivity, thermal expansion coefficient (TEC), and reactivity with gadolinia-doped ceria (GDC) or yttria-stabilized zirconia (YSZ) were studied. Reflections from SrZrO3 (similar to 6 wt %) after beat-treatment of the SYCM:YSZ mixture at 900 degrees C for 48 h and no reaction after heat-treatment with GDC were observed. In the low and intermediate temperature region (473-873 K), the TEC value is 13.3 ppm K-1 and most closely matches the common IT-SOFC electrolyte material GDC but the TEC value increases to 19.6 ppm K-1 at 873-1073 K. The investigations of the electrochemical properties of the model SOFCs at 900 degrees C with the SYCM cathode show that substituting the SYCM cathode for the standard (La,Sr)MnO3 cathode improves the cell performance. (C) 2009 The Electrochemical Society. (DOI: 10.1149/1.3184152] All rights reserved.