No abstract

High-performance organic composite thermoelectric (TE) materials are considered as a promising alternative for harvesting heat energy. Herein, composite films of poly (3,4-ethyienedioxythiophene):poly(styrene sulfonate)/single-walled carbon nanotubes (PEDOT:PSS/SWCNTs) were fabricated by utilizing a convenient solution mixing method. Thereafter, the as-prepared hybrid films were treated using sulfuric acid (H2SO4) to further optimize the TE performance. Film morphological studies revealed that the sulfuric acid treated PEDOT:PSS/SWCNTs composite samples all possessed porous structures. Due to the successful fabrication of highly conductive networks, the porous nano-architecture also exhibited much more excellent TE properties when compared with the dense structure of the pristine samples. For the post-treated sample, a high power factor of 156.43 μW⋅m−1⋅K–2 can be achieved by adjusting the content of CNTs, which is approximately 3 orders of magnitude higher than that of the corresponding untreated samples (0.23 μW⋅m−1⋅K–2). Besides, the obtained films also showed excellent mechanical flexibility, owing to the porous nanostructure and the strong π–π interactions between the two components. This work indicates that the H2SO4 treatment could be a promising strategy for fabricating highly-flexible and porous PEDOT:PSS/SWCNTs films with high TE performances.