Enhancing Thermoelectric Power Factor of Cu2-xTe Nanowires with Isoelectronic Se Doping

Cu(2-x)SeyTe(1-y) (y = 0, 0.1, 0.2, 0.5) nanowires are prepared by a facile hydrothermal method. The bulk nanostructured Cu(2-x)SeyTe(1-y) films exhibit simultaneously improved electrical conductivity and Seebeck coefficient, which result in a dramatic enhancement in power factor, compared with that of the bulk nanostructured Cu2-xTe film from room temperature to 563 K. The better thermoelectric properties of the Cu(2-x)SeyTe(1-y) films are contributed to the more grain boundaries, Te deficiency and lattice distortion. The power factor of the Cu2-xSe0.5Te0.5 sample is 160 times as much as that of the bulk nanostructured Cu2-x Te sample at 563 K. Our experiments indicate that the thermoelectric properties of the bulk nanostructured copper tellurides can be improved by isoelectronic Se doping.