Strong Phonon Scattering by Layer Structured PbSnS2 in PbTe Based Thermoelectric Materials

The incorporation of PbSnS2 in PbTe results in a tremendous reduction of the lattice thermal conductivity to 0.8 W/mK at room temperature, a reduction of almost 60% over bulk PbTe. Transmission electron microscopy reveals very high density displacement layers, misfit dislocations, and phase boundaries. Our thermal transport calculations based on modified Debye‐Callaway model, well in agreement with the experimental measurements, reveal that the layer structured PbSnS2 plays an important role in reducing the lattice thermal conductivity.