A solid oxide fuel cell having a plurality of planar layered fuel cell units, an electrically conductive flow separator plate disposed between each of the fuel cell units, and a cathode contact material element disposed between each cathode electrode of the fuel cell units and each electrically conductive flow separator plate. The cathodes of the individual fuel cell units are modified such that the operating temperatures of the cathodes are matched with the temperatures they experience based upon their locations in the fuel cell stack. The modification involves adding to the cathode contact material and/or cathode at least one alloying agent which modifies the temperature of the cathode electrodes based upon the location of the cathode electrodes within the fuel cell stack. These alloying agents react with a component of the cathode electrode to form alloys.