Synthesis of highly textured Ca3Co4O9 ceramics by spark plasma sintering

Highly textured Ca3Co4O9 ceramics were successfully prepared by spark plasma sintering using plate-like Ca3Co4O9 particles synthesized by the citrate sol–gel method. The microstructure and electrical properties of the samples were investigated. The results show that spark plasma sintering is an effective technology to prepare textured Ca3Co4O9 ceramics and that the electrical conductivity of the textured Ca3Co4O9 ceramics is anisotropic in various directions. At 700 °C, the electrical resistivity of the sample parallel to the press direction is 6.13 × 10−5 Ω m, which is a very low value reported so far.