Thermoelectric characteristics of the (Bi,Sb)2(Te,Se)3 nanocomposites processed with nanoparticle dispersion

Abstract The p-type (Bi 0.2 Sb 0.8 ) 2 Te 3 and the n-type Bi 2 (Te 0.9 Se 0.1 ) 3 thermoelectric nanocomposites were processed with dispersion of multi-walled carbon nanotubes and Al 2 O 3 nanopowders. The lattice thermal conductivity κ ph of the p-type (Bi,Sb) 2 Te 3 was effectively reduced from 0.64 W/m K to 0.45–0.54 W/m K by dispersion of carbon nanotubes. The room-temperature figure-of-merit of the p-type (Bi,Sb) 2 Te 3 was improved from 3.37 × 10 −4 /K to 3.52 × 10 −4 /K with dispersion of 0.05 vol.% carbon nanotubes. The figure-of-merit of the n-type Bi 2 (Te,Se) 3 at 75 °C was substantially improved from 2.9 × 10 −4 /K to 3.5 × 10 −4 /K with dispersion of 0.5 vol.% Al 2 O 3 nanopowders.