Recent advances in engineering electronic and thermal properties of PEDOT:PSS for efficient thermoelectric energy conversion

Abstract

Conjugated polymer based thermoelectric (TE) devices offer a promising, sustainable power source for wearable devices, with inherent advantages such as low-cost, flexibility, and low thermal conductivity (κ). Among them, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has garnered significant attention due to its excellent tunability that allows effective optimization of its TE figure of merit (ZT). Over the past decade, various processing methods—beyond conventional doping strategies—have been proposed to optimize the power factor (PF) while reducing κ. These advancements have steadily improved the TE performance of PEDOT:PSS closer to that of classical inorganic materials, highlighting the need for a comprehensive review to consolidate recent progress and explore future directions. In this review, contemporary approaches to engineering the electronic and thermal properties of PEDOT:PSS for advancing its TE performance are explored. The underlying mechanism by which these methodologies enhance the PF and reduce κ is examined, along with a discussion of exemplary breakthroughs that have leveraged these approaches to achieve high performance. The current limitations and future considerations of PEDOT:PSS-based TE are finally discussed, providing insights into potential pathways to surpass the current ZT levels.