Microstructure and thermoelectric properties of n-type 95%Bi2Te3–5%Bi2Se3 alloy produced by rapid solidification and hot extrusion

n-type SbI3-doped 95%Bi2Te3+5%Bi2Se3 compounds were prepared by a rapid solidification and extrusion at the temperature range 420–480 °C using an extrusion ratio of 25:1. The microstructure and thermoelectric properties of the compounds were investigated as a function of extrusion temperature. The fabricated powder consists of homogeneous Bi2Te3+Bi2Se3 solid solution and the relative density of over 99% was obtained by hot extrusion. The values of Seebeck coefficient for the compounds hot extruded at 420, 450, and 480 °C were −160.8, −170.2, and −165.7 μV K−1, respectively. The values of electrical resistivity (ρ) for the compounds hot extruded at 420, 450, and 480 °C were 0.49, 0.57, and 0.51×10−5 Ω m, respectively. The maximum power factor value of the compounds hot extruded at 480 °C was 53.8×106 μW cm−1 K−2.