Largely Enhanced Figure of Merit for CoSb3 Thermoelectric Material by Introducing Disordered Structure

To enhance the Seebeck coefficient and reduce the thermal conductivity and meanwhile keep an excellent electrical conductivity, the disordered structure was introduced into the ordered CoSb3 nanocrystalline by increasing hot-pressing temperature. The results show that the introduced disordered structure can increase the Seebeck coefficient from 125 VK-1 to 390 VK-1 measured at 773K, the thermal conductivity can be reduced from 1.94 Wm-1K-1 to 1.73 Wm-1K-1. Even though the electrical conductivity is decreased from 74000 Sm-1 to 14000 Sm-1, a largely enhanced figure of merit of 1.21 at 773 K still can be obtained for the sample hot-pressed at 943 K. Therefore, introducing the disordered structure into an ordered structure can be considered as an effective way to enhance the figure of merit.