Improved thermoelectric figure of merit in n-type CoSb_3 based nanocomposites

摘要

Nanocomposites offer a promising approach to incorporate nanostructured constituents to bulk thermoelectric materials, n-type CoSb_3 nanocomposites were prepared by hot pressing the mixture of nanoscale and microsized CoSb_3 powders synthesized by solvothermal method and melting, respectively. Microstructure analysis shows that the bulk materials are composed of nano- and micrograins. The nanocomposite structures are effective in reducing thermal conductivity more than electrical conductivity, hence in improving the thermoelectric performance. A dimensionless figure of merit of 0.71 is obtained for the nanocomposite with 40 wt % nanopowder inclusions, about 54% increase of that without nanopowder inclusions.