First principles study of ternary skutterudites

Abstract

As the demand of sustainable energy technologies increases in recent years, thermoelectric materials can potentially become a solution by increasing energy efficiency in certain systems, such as waste heat recovery system. Skutterudites is a popular group of thermoelectric materials because they show low thermal conductivity with filled voids in their structures. To investigate the potential of ternary skutterudites as thermoelectric materials, first-principles calculations are performed on filled and unfilled CoSn1.S1.S5, CoSn1.5Se1.5, CoSn1.5Te1.5, CoGe1.5S1.5, CoGe1.5Se1.5, and CoGe1.5Te1.5. Alkaline-earth metal and Lanthanum are used as void fillers in this study. Transport properties, including Seebeck coefficient and electrical conductivity, are obtained from Boltzmann transport theory. The calculation results show high Seebeck coefficients and low electrical conductivities. Future work will focus on increasing the electrical conductivity while reducing the thermal conductivity with appropriate filling.