Individual Adjustment of Electrical Conductivity and Thermopower Enabled by Multiple Interfaces in Polyaniline‐Based Ternary Hybrid Nanomaterials for High Thermoelectric Performances

Abstract

AbstractRecent developed conducting polymer based hybrid thermoelectric (TE) materials provide a promising alternative route for energy conversion on a large scale. However, high thermopower largely relies on high content of low‐abundance elements, such as tellurium, which impedes the mass production of these materials. To optimize the compositions of the hybrids and further improve the TE properties, interfacial engineering is therefore employed to modulate the carrier transport properties in rationally designed multiwalled carbon nanotubes (MWCNTs)‐Te nanorod/polyaniline (PANI) ternary hybrid nanomaterials considering the similar π–π conjugated interactions among these constituents. The effects of MWCNTs and Te nanorods, especially the multiple interfaces formed between the constituents, on the TE performances and carrier transport behavior are studied in depth. Due to simultaneous increase in both electrical conductivity and thermopower, an optimal power factor of 54.4 µW m−1 K−2 is obtained in 52%Te‐16% MWCNT/PANI film, which is almost twice the value of binary Te/PANI film at the same Te content and comparable to that of 60% Te/PANI film. Moreover, the ternary hybrid film shows good mechanical stability. This study demonstrates an effective strategy to improve TE performances of conducting polymer based hybrids and has great potential for cost‐effective flexible energy conversion devices.