Thermal conductivity of PbTe–CoSb₃ bulk polycrystalline composite: role of microstructure and interface thermal resistance

Systematic experimental and theoretical research on the role of microstructure interface thermal resistance conductivity PbTe-CoSb3 bulk polycrystalline composite is presented. In particular, correlation between particle size dispersed phase (R_{int}) phonon (\kappa_{ph}) discussed. With this aim, a series PbTe-CoSb_3 materials with different sizes CoSb_3 was prepared. The structural (XRD) microstructural analysis (SEM/EDXS) confirmed assumed chemical compositions. acoustic impedance difference (\Delta Z) determined from measured sound velocities in PbTe phases. calculated using Debye model agrees R_{int}. It shown that \kappa_{ph} may be reduced when (CoSb_3) smaller than critical value ~230nm. This relationship concluded to crucial for controlling heat transport phenomena thermoelectric materials. selection components elastic properties (acoustic impedance) Kapitza radius leads new direction engineering TE designed