Solvothermal synthesis and electrical transport properties of skutterudite CoSb3

Nanosized binary skutterudite CoSb3 powders were prepared by solvothermal method using CoCl2 and SbCl3 as precursors and NaBH4 as reductant. Different reaction temperatures and reaction time were studied to pursue pure CoSb3. Single CoSb3 phase was synthesized at the reaction temperature of 250 °C for 72 h. Transport properties measurements indicate the as-prepared CoSb3 has n-type conduction and a maximum power factor of 1.6 × 10−3 W m−1 K−2 is found at about 550 K without any further optimization.