Enhanced Thermoelectric Properties of Graphene/Cu3SbSe4 Composites

Incorporating a nanophase into a matrix is an effective approach to improve thermoelectric (TE) properties of bulk TE materials. In this study, graphene nanosheets were introduced into a Cu 3 SbSe 4 matrix and graphene/Cu 3 SbSe 4 composites were prepared by ball milling and rapid hot-press sintering. Microstructure and thermoelectric transport properties of graphene/Cu 3 SbSe 4 composites were analyzed. It was found that the graphene distributed uniformly in the form of layers at the grain boundaries of Cu 3 SbSe 4 matrix. The electrical conductivity of graphene/Cu 3 SbSe 4 composites increased significantly while the Seebeck coefficient decreased with the increasing content of graphene. The thermal conductivity was effectively depressed due to the enhancement of phonon scattering. The maximum thermoelectric dimensionless figure of merit was 0.75 for 2.00% graphene/Cu 3 SbSe 4 composite at 650 K, which was 3.85 times higher than that of pure Cu 3 SbSe 4 .