Flexible thermoelectric generator with polydimethyl siloxane in thermoelectric material and substrate

Abstract

In this paper, the fabrication and characterization of a flexible thermoelectric generator (TEG) is presented. Bismuth telluride powder (Bi/Te) is utilized as p- and n-type thermoelectric materials, and carbon nanotubes (CNTs) are used to enhance electrical conductivity. Both the CNTs and bismuth telluride (Bi/Te) powder are mixed with a solution of polydimethyl siloxane (PDMS) as a precursor. The same PDMS used for the hybrid thermoelectric materials is also used as the substrate, making the TEG flexible and increasing its stability. The Seebeck coefficients of the fabricated p- and n-type thermoelectric materials are 143 and -174 μV/K, respectively. The output voltage of the fabricated device is 920 mV and the generated power is 570 μW/cm2 with a temperature difference of 60 °C. The fabricated TEG maintains its performance level during bending reliability tests on a curvature with a radius as small as 5 mm, and after more than 1000 repetitions of bending on a curvature with a radius of 20 mm.