Fabrication and Characterization of Novel Nanostructured Thermoelectric Materials

Abstract

The enormous demand of energy across the world due to the advancement of technology puts a lot of pressure on fossil fuels as conventional energy sources. Also, burning of fossil fuels causes air pollution and has destructive impact on the environment. Hence, there is a need of developing suitable alternative energy production technologies which are low cost, efficient and environmental friendly. It is very important to develop the technology of energy conversion devices which are derived from solar, wind, geothermal and thermoelectrics (TE). Using the existing TE device technology the efficiency of a device can be improved by trapping the waste heat. Solid state TE devices can be used in a wide range of applications such as waste heat recovery, air conditioning, power generation and refrigeration. Thermoelectric devices have an advantage that they are acoustically silent and have no moving parts, hence they require minimum maintenance. However, TE devices find their place in niche applications in which their features can be more appropriate and capable. newlineTwo devices, one from PbTe bulk and the other from PbTe bulk nanocomposite were fabricated. It was observed that device performance is significantly enhanced in bulk nanocomposites as compared to bulk. This enhancement is due to nano inclusions which affect the scattering of the charge carriers diffusing from the hot side to cold side. The maximum voltage drawn from the bulk-nanocomposite device was ~ 25 mV at 550 °C and maximum current produced by the device was ~ 10 mA. newline