PbTe has proven to be a very important intermediate thermoelectric material.
In order to improve the thermoelectric performance of materials, the power factor (
Other n-type doping agents such as Bi2Te3, TaTe2, MnTe2, will substitute for Pb and create uncharged vacant Pb-sites.
These sites are filled by Te atoms which are ionized to create additional positive holes.
[6] With band gap engineering, the maximum zT of PbTe has been reported to be 0.8 - 1.0 at ~650K.
Collaborations at Northwestern University boosted the zT of PbTe by significantly reducing its thermal conductivity using ‘all-scale hierarchical architecturing'.
[7] With this approach, point defects, nanoscale precipitates and mesoscale grain boundaries are introduced as effective scattering centers for phonons with different mean free paths, without affecting charge carrier transport.
By applying this method, the record value for zT of PbTe that has been achieved in Na doped PbTe-SrTe system is approximately 2.2.