Thermoelectric Transport Properties of Interface-Controlled p-type Bismuth Antimony Telluride Composites by Reduced Graphene Oxide

Abstract

We report the thermoelectric transport properties of interface-controlled p-type bismuth antimony telluride (BST) composites using reduced graphene oxide (rGO). The composites were prepared by the spark plasma sintering (SPS) of BST–graphene oxide (GO) hybrid powder, which could induce the in situ reduction of GO into rGO. Compared to the pristine BST, the interface-controlled BST composites exhibited degraded electrical conductivities with similar Seebeck coefficients, consequently resulting in decreased power factors. However, thanks to the suppressed lattice thermal conductivity by the rGO network at the grain boundaries, this disadvantage could be compensated in terms of ZT. Our results will be helpful for understanding thermoelectric transport properties of various graphene-hybrid thermoelectric materials.