Enhanced thermoelectric power factor and low thermal conductivity in one-dimensional Te/Ag2Te composites

We reports the synthesis and characterization of Te/Ag2Te nanorod composites with various Ag2Te contents. The composite samples were prepared by mixing Te and Ag2Te nanorods synthesized by polyvinylpyrrolidone (PVP)-assisted solution-phase mixing. The thermoelectric properties of the prepared composites vary according to the Ag2Te content. Furthermore, the samples exhibit an enhancement in electrical conductivity and a reduction in the Seebeck coefficient with increasing Ag2Te content. The maximum power factor (350.71 mu V/K at room temperature) is observed for the sample containing 30% Ag2Te. The samples were assembled as 1D nanostructures, which led to a decrease in thermal conductivity owing to the strong phonon scattering effect. The maximum thermoelectric figure of merit (ZT) at room temperature, 0.34 was obtained for the sample with 30% Ag2Te content. This value is 480% larger than that obtained for the pristine Te nanorod samples.