Thermoelectric properties of TiS2-xPbSnS3 nanocomposites

Thermoelectric properties of micro-scale n-type TiS2 ceramics containing p-type PbSnS3 nanoparticles were investigated from 350 to 650 K. The addition of PbSnS3 caused a substantial enhancement of Seebeck coefficient and a decrease of electrical conductivity, primarily due to the decrease of carrier concentration, while keeping power factor almost non-deteriorated with PbSnS3 no more than 1 mol% in the composite. The electrical thermal conductivity was decreased with PbSnS3 addition. Moreover, the lattice thermal conductivity was suppressed most in the composite with 0.5 mol% PbSnS3 which was nano-scale dispersed mainly along the TiS2 grain boundaries. As a result, a maximum zT similar to 0.44 at 650 K was obtained in TiS2-0.5mol% PbSnS3, ranking among the tops for TiS2-based thermoelectrics so far. (C) 2016 Elsevier B.V. All rights reserved.