Fe-Doping Effect on Thermoelectric Properties of p-Type Bi0.48Sb1.52Te3

Abstract

The substitutional doping approach has been shown to be an effective strategy to improve <i>ZT</i> of Bi₂Te₃-based thermoelectric raw materials. We herein report the Fe-doping effects on electronic and thermal transport properties of polycrystalline bulks of <i>p</i>-type Bi_0.48Sb_1.52Te₃. After a small amount of Fe-doping on Bi/Sb-sites, the power factor could be enhanced due to the optimization of carrier concentration. Additionally, lattice thermal conductivity was reduced by the intensified point-defect phonon scattering originating from the mass difference between the host atoms (Bi/Sb) and dopants (Fe). An enhanced <i>ZT</i> of 1.09 at 300 K was obtained in 1.0 at% Fe-doped Bi_0.48Sb_1.52Te₃ by these synergetic effects.