Enhanced thermoelectric properties of Pb1−xBixS prepared with hydrothermal synthesis and microwave sintering

Abstract

As a cheap substitute for PbTe or PbSe, the thermoelectric performance of PbS still remains to be improved. In this report, we selected Bi₂S₃ as a donor and employed a facile route of hydrothermal synthesis combined with microwave sintering to fabricate Bi₂S₃ doped PbS. Due to the increased electrical conductivity by Bi₂S₃ doping and the decreased thermal conductivity from the refined microstructure, the thermoelectric figure of merit ZT of microwave sintered Pb_0.995Bi_0.005S and Pb_0.99Bi_0.01S reached 0.90 and 0.86 at 800 K, respectively, without sign of saturation. When processed with plasma activated sintering (PAS), the highest ZT value of Pb_0.99Bi_0.01S only reached 0.3 at 800 K. The obtained results indicate that hydrothermal synthesis and microwave sintering can essentially improve the thermoelectric properties of Pb_1−xBi_xS and easily realize mass production at low cost.