• Gayner, Chhatrasal
• Das, Malay K.
• Kar, Kamal K.

Abstract

<p>The electrical and thermal transport properties of Ni-doped PbSe (PbSe:Ni_x; 0.01�≤�x�≤�0.06) have been studied. Further, the complex crystal chemistry of Pb-substitutional/tetrahedral interstitial site occupancy of Ni has been studied to understand the influence of divalent dopants on the thermoelectric transport properties of PbSe. Ni incorporation in PbSe introduces Ni impurity bands located near the valence band and also induces bandgap narrowing (BGN) by shifting the Fermi level deep into the valance band. This affects the charge carrier transport to decrease the resistivity and to maintain high Seebeck coefficient of ∼230�μV/K. Again, the disorder created by dopant atoms leads to anharmonic lattice vibrations responsible to the lower lattice thermal conductivity in PbSe:Ni_xas compared to that of the pristine PbSe. The concurrently increased electrical conductivity and decreased thermal conductivity enhance the thermoelectric performance of PbSe:Ni_0.04by increasing its power factor and figure of merit to 142% and 180% of the corresponding values for the pristine PbSe.</p>

Topics

• resistivity
• interstitial
• thermal conductivity
• electrical conductivity