High performance of PEDOT:PSS/SiC-NWs hybrid thermoelectric thin film for energy harvesting

Abstract

A nanoscale organic/inorganic hybrid thin film has been fabricated with the conductive poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) and SiC nanowires (SiC-NWs) defined as PEDOT:PSS/SiC-NWs by a facile dilution-filtration method and the thermoelectric (TE) performance has been investigated systematically. It has been demonstrated that a low content of SiC-NWs (<10 wt%) can effectively enhance the Seebeck coefficient of PEDOT:PSS films by 36.6% (20.9 μV K−1) with maintaining a high electrical conductivity of 1550 S cm−1. A high power factor of 67.7 μW m−1 K−2 for the PEDOT:PSS/SiC-NWs with 3.0 wt% high purity SiC-NWs (p-SiC-NWs) was obtained and further enhanced to 128.3 μW m−1 K−2 after H2SO4 post-treatment, which is two times higher than that of pre-treatment and four times higher than that of pure PEDOT:PSS (31.8 μW m−1 K−2). Based on the thermal conductivity measured to be 0.23 W m−1 K−1, the maximum ZT value was achieved as high as 0.17. Finally, a flexible TE generator has been designed and fabricated by parallel connected ten legs of the as-prepared H2SO4 post-treated PEDOT:PSS/p-SiC-NWs3 hybrid thin films. The maximum open-circuit voltage of 21.9 mV and output power of 180 nW at ΔT = 100 K were obtained, which show great potential for the flexible TE generator development.