Synthesis and thermoelectric properties of p-type Zn-doped ZnxIn1−xSb compounds

P-type Zn-doped ZnxIn1−xSb(0 ⩽ x ⩽ 0.10) compounds with different Zn content are synthesized by slow growth from melt. The effects of Zn content on the structure and thermoelectric properties are investigated. The results show that all the specimens exhibit p-type conduction characteristics. The solubility limit of Zn doping in ZnxIn1−xSb is found to be close to 0.05. The room-temperature carrier concentration Np of the samples increases obviously with increasing Zn content for the Zn-doped ZnxIn1−xSb compounds, while the room-temperature carrier mobility and the thermal conductivity decrease with increasing Zn content for the Zn-doped ZnxIn1−xSb compounds. The Zn-doped ZnxIn1−xSb compounds possess a high power factor. The maximum power factor of 2.44×10−3 W m−1 K−2 is obtained at 460 K for Zn0.0075In0.9925Sb compound. The maximum ZT value of 0.27 is obtained at 700 K for Zn0.01In0.99Sb due to the lower thermal conductivity and higher power factor.