Facile fabrication of one-dimensional Te/Cu(2)Te nanorod composites with improved thermoelectric power factor and low thermal conductivity

In this study, Te/Cu(2)Te nanorod composites were synthesized using various properties of Cu(2)Te, and their thermoelectric properties were investigated. The nanorods were synthesized through a solution phase mixing process, using polyvinylpyrrolidone (PVP). With increasing Cu(2)Te content, the composites exhibited a reduced Seebeck coefficient and enhanced electrical conductivity. These characteristic changes were due to the high electrical conductivity and low Seebeck coefficient of Cu(2)Te. The composite containing 30 wt.% of Cu(2)Te nanorods showed the maximum power factor (524.6 μV/K at room temperature). The two types of nanorods were assembled into a 1D nanostructure, and with this structure, thermal conductivity decreased owing to the strong phonon scattering effect. This nanorod composite had a dramatically improved ZT value of 0.3, which was ~545 times larger than that of pristine Te nanorods.