Solidification contraction-free synthesis for the Yb0.15Co4Sb12 bulk material

The solidification contraction and feeding ability of Yb partially filled CoSb3 skutterudite alloys were studied in this letter. It is found that the pore formation was mainly due to the large solidification contraction during the L+CoSb→CoSb2 peritectic phase transition and the primary dendrite networks. Homogeneous and full density Yb0.15Co4Sb12 bulk material was synthesized directly from the peritectic phase transition L+CoSb2→CoSb3 by controlling the melting temperature and starting materials. The result of thermoelectric property measurement from room temperature to 500°C shows that the thermoelectric dimensionless figure of merit reaches to the maximum of 0.7 at 400°C.