Abstract
Effects of doping on the thermal conductivity of CoSb3 have been investigated using Ni, Pd and Pt as donor impurities. The lattice thermal conductivity decreases with increasing carrier concentration, almost independently of these impurities. The lattice thermal conductivity as low as 0.04 Wcm-1K-1 can be achieved by heavy doping (the carrier concentration range is more than 1020cm-3). The comparison of results to theoretical calculations indicates that the coupling of point-defect (alloy) scattering with electron-phonon scattering plays an important role in reducing the lattice thermal conductivity. However, the degrees of these two scattering effects for Ni doping are essentially different from those for Pd or Pt doping due to the impurity dependence of material properties (atomic mass, atomic size, deformation potential, and carrier effective mass).
