Enhancement of the thermoelectric properties of directionally grown Bi-Ca-Co-O through Pb for Bi substitution

Thermoelectric performances on cobaltite ceramics can be changed by doping followed by grain orientation methods. This can be performed by the Laser Floating Zone (LFZ) method on samples with different substitutions in the Rock Salt sublattice. In this work, Bi2-xPbxCa2Co1.7Oy (x=0.0, 0.2, 0.4 and 0.6) ceramics have been directionally grown at 30mm/h. In all the cases, samples show a microstructure composed, mainly, of alternated grains of the thermoelectrical phase and the solid solution Bi(Pb)-Ca-O, with small CoO inclusions. It has been found an important improvement on the resistivity and thermopower for samples with 0.4 Pb substitution, leading to power factor values higher than usual in misfit cobaltites obtained by conventional solid state routes. © 2010 Elsevier Ltd.The authors wish to thank the Gobierno de Aragón (Research Groups T12 and T74, and project PI154/08), the Spanish Ministry for Education and Science (Spanish–French Integrated Action HF2006-0171), and the Spanish Ministry of Science and Innovation (ProjectMAT2008-00429) for financial support.Peer Reviewe

Enhancement of the thermoelectric properties of directionally grown Bi–Ca–Co–O through Pb for Bi substitution

International audienc

Enhancement of the thermoelectric properties of directionally grown Bi–Ca–Co–O through Pb for Bi substitution

International audienc