Effect of the Addition of Copper Particles on the Thermoelectric Properties of the Ca3Co4O9 + δ Ceramics Produced by Two-Step Sintering

Abstract Composite thermoelectric materials based on layered calcium cobaltite Ca 3 Co 4 O 9 + δ doped with copper particles were synthesized by two-step sintering, and their microstructure, electrotransport properties studied. It was determined that the introduction of into ceramics improves sinterability at moderate sintering temperatures ( T sint ≤ 1273 K), leading to a decrease in porosity samples an increase electrical conductivity power factor, whereas oxidation less conductive copper(II) oxide significantly decreases factor sintered elevated ≥ 1373 K). The is maximum for wt % Cu ceramic K (335 μW/(m 2 ) temperature 1100 which 2.3 higher than base material same thermal history (145 K) more times 9+δ conventional solid-phase method.