Thermoelectric Properties of <scp>ZnO NR</scp> / <scp>PEDOT</scp> : <scp>PSS</scp> on <scp>PET</scp> Substrates for Flexible Devices

ABSTRACT This article demonstrates the thermoelectric properties of ZnO nanorods (NRs)/poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate) (PEDOT:PSS) composites films on a flexible ITO substrate. Compact ZnO thin films and ZnO NRs have been grown by the cost‐effective sol–gel method. The thermoelectric properties of both films have been investigated along with thermophysical characteristics. X‐ray diffraction reveals the hexagonal wurtzite growth of ZnO nanostructures. The temperature‐dependent thermal characteristics for both composites have been investigated through the transient plane source method in the temperature range of 303–353 K. The thermal conductivity of the compact ZnO/PEDOT:PSS composite is found to be in the range of 1.30–1.33 W/mK, whereas a significant enhancement in thermal conductivity is observed in the ZnO NRs/PEDOT:PSS composite film, which is attributed to phonon scattering and interfacial transport through vertically aligned nanorods. Compared with earlier ZnO‐polymer composites reported in the literature, this work highlights the unique influence of ZnO NRs/PEDOT:PSS morphology on thermoelectric behavior in flexible films. Our study reveals that these composites could be beneficial for low‐temperature waste heat management devices.