Development of a new thermoelectric Bi2Ca2Co1.7Ox + Ca3Co4O9 composite

Bi2Ca2Co1.7Ox nominal composition ceramic rods were textured by the electrically assisted laser floating zone technique. A new composite formed by three phases, two of them with well-known thermoelectric properties, Bi2Ca2Co1.7Ox and Ca3Co4O9, was obtained for the first time when the growth process was performed with a 300 mA applied current. Under these conditions the thermoelectric performances of this new composite reach values above the highest ones reported in the literature for polycrystalline Bi2Ca2Co1.7Ox materials.