Fabrication of one-dimensional Cu2Te/Te nanorod composites and their enhanced thermoelectric properties

Abstract

Cu₂Te/Te nanorod composites were fabricated and their thermoelectric properties were investigated. The composites were prepared by simple mixing of two different types of nanorods, which were synthesized by solution mixing with PVP. The thermoelectric power factor of the Cu₂Te/Te nanorod composites at room temperature was the highest (430.58 μV K⁻¹) at 10 wt% Te. The enhancement in power factor is indicated by the change in electrical conductivity and Seebeck coefficient. Additionally, the composites have a 1D nanostructure, which can greatly reduce the total thermal conductivity of the composites owing to the strong phonon scattering effect. Because of the enhancement in power factor and decrease in thermal conductivity, the composite samples show an enhanced thermoelectric figure of merit (ZT). The maximum ZT of the Cu₂Te/Te nanorod composites was 0.22, which was achieved for a Te content of 10 wt% and was ∼4.5 times larger than that of the pristine Cu₂Te nanorods.