Effect of tin content on thermoelectric properties of p-type lead tin telluride

Pb1-xSnxTe single crystals with various Sn contents (x) were prepared by the Bridgman method. Electrical conductivity (sigma), hole concentration (p), Seebeck coefficient (alpha), and thermal conductivity (kappa) were measured in the temperature range of 300-700 K, All samples showed p-type conduction at 300 K. Hole concentration at 300 K changed from 3.1 x 10(24) to 5.0 x 10(26) m(-3) as alpha changed from 0.0 to 1.0. The alpha values of all samples showed a maximum at a certain temperature and the temperature at the maximum of alpha shifted to the high temperature side with increasing Sn content. The lattice thermal conductivity had the minimum at x = 0.5. Figure of merit (Z) reached its maximum at a certain temperature (T-opt), and the T-opt shifted to the high temperature side with increasing Sn content. (C) 2000 Elsevier Science Ltd. AU rights reserved.