Fabrication of Thermoelectric Module from Efficient Earth Abundant Thermoelectric Materials

Abstract

To develop a power generation technology, we proposed low-cost and nontoxic earth abundant thermoelectric materials consisting of n-type and p-type iron oxides. For high temperature applications of power generation, thermoelectric materials consisting of oxide assure better thermoelectric properties. In this research work, thermoelectric module has been fabricated with three pairs of p-type and n-type thermoelectric materials. In this context, we used Hematite (α-Fe2O3) as thermoelectric material which is naturally n-type. By doping Zn, α-Fe2O3 turned into p-type. Using spin coating method, n-type α-Fe2O3 and p-type Zn doped α-Fe2O3 (Zn:αFe2O3) have been synthesized. For the p-type and n-type legs of the thermoelectric module, the dense bulk samples of α-Fe2O3 have been produced by cold isostatic pressing at 450 MPa for 15 min. Six-leg thermoelectric module consisting of three pairs of n-type α-Fe2O3 and p-type Zn:α-Fe2O3 bulks of 3 × 5 mm2 cross-section and heights of 10.5 mm were fabricated. At an operating temperature of 893 K with a temperature difference of 471 K, an open circuit voltage of 744 mV was generated.