Thermoelectric Properties of Fe^sub 1+y^Te Prepared by a High Pressure Sintering Method

Enhancing thermoelectric properties by utilizing topological properties of topological insulators has attracted increasing attention. Here, powder metallurgy technology combined with high pressure sintering (HPS) was used to prepare Fe1+yTe (y = 0.1, 0.15, 0.1978, 0.22) alloys at 1173 K. The prepared products were identified by x-ray diffraction, and their microstructures were examined by field-emission scanning electron microscopy (FE-SEM). Electric conductivities (σ) and Seebeck coefficient (S) were measured in the temperature range of 303-623 K. The influence of variation in Fe content on thermoelectric properties was studied. The experimental results show that all HPS samples are nanometer composites consisting of Fe3Te2 and FeTe2. Fe1+yTe have electrical charges on the boundaries of topological insulators, which have the potential to be studied in the future. The Fe1+yTe with y = 0.1 shows the best thermoelectric properties at room temperature.