Enhanced thermoelectric figure of merit in p-type BiSbTeSe alloy with ZnSb addition

Abstract

We have prepared p-type BiSbTeSe alloys with different ratios of ZnSb addition by a zone melting method. The microstructure characterization shows that a second phase of ZnSeTe was generated in the matrix. Due to the ZnSb addition, the carrier concentration was increased, thus improving the electrical performance (power factor, α²σ), while the lattice thermal conductivity (κ_L) was simultaneously decreased, mainly due to the introduced defects, such as anti-site substitution, the second phase and interfaces with different scales. As a result, a significant improvement in the thermoelectric figure of merit ZT was obtained, especially above 370 K, which is very beneficial for commercial applications in power generation.