ICT2014 Abstracts

Nanostucturing and a second phase incorporation are considered promising ways to enhance the thermoelectric performance of bulk materials. Here, a design principle of combining these two ways to improve the thermoelectric performance of p-type CoSb₃ is proposed by fabricating a CoSb₃/graphene (CoSb₃/G) nanocomposite, where a second phase, graphene, is introduced in the nanostructured CoSb₃ matrix via an in situ one-pot solvothermal route. And CoSb₃/G bulk materials were prepared by hot pressing the solvothermally synthesized CoSb₃/G powder. It was found that a small amount of graphene (1.5 wt%) can drastically enhance the electrical conductivity due to the increase in both carrier concentration and mobility. In addition, the well dispersed graphene in nanostructured CoSb₃ matrix also contribute to the low lattice thermal conductivity. A dimensionless figure of merit ZT = 0.61 at 800 K has been obtained for the CoSb₃/G nanocomposite, about 130% improvement over that of graphene-free CoSb₃ (~0.26).