PEDOT-based thermoelectric composites: Preparation, mechanism and applications

Thermoelectric (TE) materials enable effective and direct energy conversions between heat and electricity, displaying wide applications including waste/low-grade heat harvesting, local cooling, sensing and wearable electronics. Among the recently-developed organic and composite TE materials, poly(3,4-ethylenedioxythiophene) (PEDOT) is perhaps the most successful and frequently reported type. Herein, we aim to review the recent advances of the synthesis, mechanism and applications of PEDOT-based TE composites. First, the research background and the history of TE materials are briefly introduced. Next, the synthesis and TE performance of PEDOT-based composites are summarized according to the sequence of films, hydrogels/aerogels and fibers/yarns. Then, the mechanism, structure and property are elucidated. After that, the recent development and its applications of power generation and sensing are highlighted. Finally, we provide an outlook on the prospects and the challenges of PEDOT-based TE composites.