Thermoelectric generation device based on p-type Si0.4Sb1.6Te3 and n-type Bi2Se0.6Te2.4 bulk materials prepared by solid state microwave synthesis

This study reports on the fabrication of a chalcogen-based thermoelectric power generation (TEG) device using p-type Bi0.4Sb1.6Te3 and n-type Bi2Se0.6Te2.4 bulk thermoelectric materials. The microstructure of the samples was characterized by scanning electron microscope (SEM). The phase composition of the powders was characterized by X-ray diffraction (XRD), revealing a rhombohedral structure. The thermoelectric (TE) properties such as the Seebeck coefficient (S) and the electrical conductivity (a) of the resulting alloys were studied in the temperature range of 300-523 K. The power factor (P-factor) for a Bi0.4Sb1.5Te3 as p-type sample was found to be 4.96 mW/mK(2) at 373 K, whereas 222 mW/mK(2) was obtained at 383 K for a Bi2Se0.6Te2.4 as n-type sample. Electrical power generation characteristics such as high open circuit voltage (V-oc) and maximum output power (P-max) were monitored by changing the temperature conditions required to generate maximum power. The significance of the resistances including the internal resistance (R-in) and contact resistance (R-c) between legs and electrodes, are discussed. The maximum output power obtained with the 9 p-n couples device was 39.4 mW under the thermal condition of T-H=523 K hot side temperature and Delta T= 184 K temperature difference. (C) 2013 Elsevier Ltd. All rights reserved.