Composite Aerogel of Electropolymerized Polyaniline and SWCNTs with High Thermoelectric Performance

Abstract Aerogels are promising in the preparation of high‐performance thermoelectric (TE) materials due to their ultralow thermal conductivity. However, the TE performance of aerogels remains unsatisfactory. Herein, polyaniline/single‐walled carbon nanotubes (PANI/SWCNT) composite aerogel with high thermoelectric performance is synthesized through dynamic three‐phase interfacial electrochemical polymerization of aniline and subsequent physical mixing of PANI with SWCNTs followed by liquid nitrogen quenching and freeze‐drying. By adjusting the content of SWCNTs, the PANI/SWCNT aerogel (50 wt% SWCNTs) achieves a high power factor (PF) of 73.33 ± 2.03 µW m −1 K −2 . The ultralow thermal conductivity of around 2.30 × 10 −2 W m −1 K −1 for the composite aerogel is superior to that of most conventional organic TE materials, rendering an excellent figure of merit ( ZT ) value of ≈0.95 at room temperature and great potential in improving TE performance of organic and organic/inorganic composites. Thermal treatment of the composite aerogel further enhances the PF to 96.28 ± 1.89 µW m −1 K −2 . This work provides an effective method in the formation of PANI/SWCNT TE composites and it puts forward insights into the preparation of other high‐performance TE composites.