Abstract
The effect of microstructure on the electrical conductivity of SrCo0.8Fe0.2O3-delta (SCFO) was investigated in air using a four-point de method. In the test temperature range of 200 to 900 degrees C, the electrical conductivity of this material was observed to increase with the increase of the average grain size in the lower temperature region where the conductivity increases with the increase of the temperature. The activation energy is decreased with the increase of the grain size in this region, 0.04 +/- 0.003 ev for 3.1 mu m sample and 0.01 +/- 0.001 ev for 14.8 mu m sample. When temperature is further increased, the conductivity of this material decreases with the increase of the temperature, and the grain size effect becomes less noticeable.