Thermoelectric properties of pressure-sintered Si0.8Ge0.2 thermoelectric alloys

Abstract

The thermoelectric properties of 28 sintered Si0.8 Ge0.2 alloys, heavily doped with either boron or phosphorus and prepared from powders with median particle sizes ranging from about 1 μm to over 100 μm, have been determined from 300 to 1300 K. The thermal conductivity decreases with decreasing particle size, however, the figure of merit is not significantly increased due to a compensating reduction in the electrical conductivity. The thermoelectric figure of merit is in good agreement with results of Dismukes et al. [J. Appl. Phys. 10, 2899 (1964)] on similarly doped alloys prepared by zone-leveling techniques. The electrical and thermal conductivity are found to be sensitive to preparation procedure while the Seebeck coefficient and figure of merit are much less sensitive. The high-temperature electrical properties are consistent with charge carrier scattering by acoustic or optical phonons.

Lattice thermal conductivity of group-IV and III–V semiconductor alloys

“…50% was attained by increasing grain boundary scattering of phonons. 22 It is clear from Fig. 4 that the present model ͓Eqs.…”

Phonon engineering through crystal chemistry

“…Point defect scattering has been successfully employed in both thermoelectic materials (Si 1-x Ge x ), and in thermal barrier coatings, such as yttria stabilized zirconia (YSZ). 1,9 In the simple case of alloying on a single crystallographic site, s PD is given by eqn (8). Here, f i is the fraction of atoms with mass m i and radius r i that reside on a site with average mass and radius m and r, respectively.…”

Copper chalcogenide thermoelectric materials

“…Data are taken from Refs. [14,16,[29][30][31]42,45,[66][67][68][69][70][71][72][73][74][75][76][77].…”