Enhancement in thermoelectric performance of n-type Pb-deficit Pb-Sb-Te alloys

Bhuvanesh Srinivasan (1) , Francesco Gucci (2) , Catherine Boussard-Plédel (1) , François Cheviré (1) , Michael J. Reece (2) , Sylvain Tricot (3) , Laurent Calvez (1) , Bruno Bureau (1)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 QMUL - Queen Mary University of London
3 IPR - Institut de Physique de Rennes

PbTe based materials are well known for their high performance thermoelectric properties. Here, a systematic study of thermoelectric transport properties of n-type Pb-deficit Pb0.98-xSbxTe alloys with carrier concentrations in the range of 10-19 cm-3 is presented from room temperature to 623 K. A maximum thermoelectric figure of merit (zT) of 0.81 was achieved at 623 K for 4 mol% Sb containing Pb-deficit composition, by the cumulative integration of enhanced power factor and significant reduction in thermal conductivity. The scattering of phonons at Pb vacancies, contributed to the reduction of lattice thermal conductivity, and thereby strikingly boosted the zT of the Pb-deficit samples when compared with the pristine Pb1-xSbxTe.

Keywords: Low thermal conductivity; Sb alloying; Pb-deficit lead tellurides; Improved figure of merit Graphical Abstract; Thermoelectrics

Domains: Chemical Sciences; Physics [physics]; Engineering Sciences [physics]

Bhuvanesh Srinivasan, Francesco Gucci, Catherine Boussard-Plédel, François Cheviré, Michael J. Reece, et al.. Enhancement in thermoelectric performance of n-type Pb-deficit Pb-Sb-Te alloys. Journal of Alloys and Compounds, 2017, 729, pp.198 - 202. ⟨10.1016/j.jallcom.2017.09.135⟩. ⟨hal-01613123⟩