Synthesis and thermoelectric properties of dual-atom filled p-type CamCenFexCo4－xSb12 compounds

The single-phase dual-atom filled p-type CamCenFexCo4-xSb12 compounds were synthesized by melting reactio n method. Effects of Ca and Ce filling fraction on the thermoelectric properties of the p-type CamCenFexCo4-xSb 12 were investigated. Our results indicate that with the same filling frac tion, carrier concentration and electrical conductivity of p-type Cam CenFexCo4-xSb12 intervene between t hat of single atom filled compounds CamFexCo4-x Sb12 and CenFexCo4-xSb12, and decreased with increasing Ca and Ce, especially Ce, filling fraction. With the same filling fraction, the lattice thermal conductivity of CamCenFexCo4-xSb12 is smaller than that of CamFexCo4-xSb12 and CenF exCo4-xSb12. Furthermore, when the total fillin g fraction (m+n) is about 0.3 and the filling fractions of Ca and Ce are approxi mately equal, the lattice thermal conductivity is the smallest. The greatest ZT value of 1.17 was obtained at 750K for p-type Ca0.18Ce0.12 Fe1.45Co2.55Sb12.21.