Material for solid oxide fuel cell, cathode including the material, and solid oxide fuel cell including the material

A material for a solid oxide fuel cell, the material including: a first compound having a perovskite crystal structure, a first ionic conductivity, a first electronic conductivity, and a first thermal expansion coefficient, wherein the first compound is represented by Formula 1 below; and a second compound having a perovskite crystal structure, a second ionic conductivity, a second electronic conductivity, and a second thermal expansion coefficient, Ba a Sr b Co x Fe y Z 1-x-y O 3-´ ,Formula 1 wherein Z is a transition metal element, a lanthanide element, or a combination thereof, a and b satisfy 0.4 ¤ a ¤ 0.6 and 0.4 ¤ b ¤ 0.6, respectively, x and y satisfy 0.6 ¤ x ¤ 0.9 and 0.1 ¤ y ¤ 0.4, respectively, and ´ is selected so that the first compound is electrically neutral.