Synergistic Strategies to Boost Lead Telluride as Prospective Thermoelectrics

Abstract

Lead telluride PbTe is a typical mid-temperature thermoelectric (TE) material, which has been intensively studied to achieve higher TE performance. We summarize three strategies that have been successfully applied in PbTe-based TE materials. The first strategy is charge carriers concentration engineering to optimize electrical transport. The optimal hole concentration for p-type PbTe is equal to (3-40) × 1019 cm-3, while for n-type PbTe, electron concentration is equal to (4-40) × 1018 cm-3, which is one order of magnitude lower than p-type. The second strategy is band engineering to enhance Seebeck coefficient. This strategy comprises band convergence, DOS distortion, resonant state, band alignment, band flattening, and impurity level. The third strategy is structural-defect engineering to lower the lattice thermal conductivity. In this part, the defects are sorted by dimensions from three-dimension to zero-dimension. At the end of the chapter, we give conclusion and prospects toward the PbTe system.