High pressure synthesis and thermoelectric properties of micro/nano structures CoSb3

Abstract

Nano-particle and defect have been proved to be effective in depressing the lattice thermal conductivity and improving the performance of thermoelectric materials. In this work, In0.5SnxCo4Sb12 were prepared using a high pressure and high temperature (HPHT) method, In and Sn was assumed that In plays the role of a filler and occupies the Sb-icosahedron voids. Doping of In and Sn results in the defects, nanostructuring, and mesoscale structuring were all combined into a single skutterudite matrix. The thermoelectric properties were measured in the temperature range of 321–710K. As expected, with the synthetic pressures increased，the thermal conductivity of samples improved significantly. The minimum value of In0.5Sn0.4Co4Sb12 synthesized at 3.8GPa is 1.79Wm−1K−1 and the highest Seebeck coefficient of sample In0.5Sn0.2Co4Sb12 synthesized at 2.8GPa reached 222μVK−1 finally.