Progress of Research on Bulk Thermoelectric Material PbTe in Foreign Countries

As a bulk thermoelectric (TE) material used in intermediate temperature ranged in 500 ~ 900 K, PbTe is one of the earliest semiconducting TE material systems that has been extensively studied.Recently, renew interests are invoked on this old material system due to the highest TE dimensionless figure-of-merit so far in bulk TE materials, ZT of 1.4 ~ 1.8.This paper reviews the recent progresses of this material system, include the energy band structure and phonon spectra, methods of Seebeck coefficient enhancing and lattice thermal conductivity suppressing, as well as the possible way of future study.