Mechanically Durable and Flexible Thermoelectric Films from PEDOT:PSS/PVA/Bi_0.5Sb_1.5Te₃ Nanocomposites

Advances in organic thermoelectric materials have focused on the enhancement of mechanical property to address the limitations and needs of forming flexible and free-standing films for the application of flexible/wearable thermoelectric devices. Herein, thermoelectric nanocomposite films are fabricated based on conductive polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), plastic reinforcer polyvinyl alcohol (PVA), and inorganic Bi_0.5Sb_1.5Te₃ thermoelectric nanocrystals with various contents. The resulting PEDOT:PSS/PVA/Bi_0.5Sb_1.5Te₃ nanocomposite films exhibit a power factor of 47.7 µW m⁻¹ K⁻² and a ZT value of 0.05 at 300 K. More importantly, they are mechanically tough, yet very flexible with a tensile strength of 79.3 MPa and a fracture strain of 32.4%, which is sufficient to meet the required mechanical properties of textile manufacturing and body movements for flexible thermoelectric films, thus providing a substantial impact on future developments of flexible/wearable energy generation devices.