The influence of CNTs on the thermoelectric properties of a CNT/Bi2Te3 composite

CNT/Bi2Te3 composites were prepared from composite powders in which CNTs were implanted in the Bi2Te3 matrix powders by a novel chemical route. It was found that the fabricated composite had a microstructure of a homogeneous dispersion of CNTs in the Bi2Te3 matrix due to interfacial bonding agents of oxygen atoms attaching to the surface of CNTs. The dimensionless figure of merit (ZT) of the composite shows significantly increased values compared to those of pure binary Bi2Te3 in the temperature range of 298–498 K and a maximum ZT of 0.85 was obtained at 473 K. It is considered that the improved thermoelectric performance of the composite mainly originated from thermal conductivity that was reduced by active phonon-scattering at the CNT/Bi2Te3 interface.