Study of thermoelectric properties of polycrystalline SnSe by Ag and Pb co-doping

Ag and Pb co-doped polycrystalline SnSe materials were prepared by melting, high-energy ball milling and hot pressing sintering successively, and then their thermoelectric properties were investigated systematically. The results show that the addition of Pb can effectively improve the conductivity. The room temperature carrier concentration of the Sn 0.94 Ag 0.01 Pb 0.05 Se sample reaches 2.9 × 10 18 cm −3 . Ag 2 Se phase was formed in the material. With the increase of Ag and Pb content, the SnSe polycrystalline grains grew significantly, resulting in the increase of thermal conductivity. The ZT value of the Sn 0.98 Ag 0.01 Pb 0.01 Se sample at 873 K is 1.4, which is lower than that of pure SnSe polycrystalline.