2017 Volume 64 Issue 8 Pages 461-466
To further enhance thermoelectric (TE) properties of higher manganese silicides (HMSs), the dissipation of layered precipitates of the MnSi phase as well as the optimization of the hole carrier concentration are critical. We have systematically studied electronic structure of partially substituted solid solutions of (Mn1−xMx)Si1.7 with M = transition metals and prepared bulk samples of such solid solutions by spark plasma sintering. A 2 at% substitution of manganese with vanadium is found to dissipate the MnSi-precipitates effectively, results in a substantial increase in electrical conductivity from 3 × 104 S/m to approximately 5 × 104 S/m at 800 K. The resulting TE power factor reaches 1.86 mW/K2m at 710 K, 30% higher than that of V-free samples.
