Enhanced Thermoelectric Performance of Carbon Nanotubes/Polyaniline Composites by Multiple Interface Engineering

Here, we put forward an effective strategy to regulate the interface structure of carbon nanotubes/polyaniline (CNTs/PANI) composite films and improve their thermoelectric (TE) properties by sequential dedoping-redoping treatment. Dedoping induces conductive resistance-undoped PANI to enhance the energy barrier between CNTs and PANI, leading to a greatly increased Seebeck coefficient and deteriorated conductivity. Subsequently, upon the redoping process, the electrical conductivity is dramatically improved owing to the generated conductive PANI chains, while Seebeck coefficient is maintained at 90% of the dedoped composites. This yields a significantly improved power factor of 407 mu W m(-1) K-2 from the as-prepared composites (234 mu W m(-1) K-2), which is the highest value among those of all the reported CNTs/PANT composites. The outstanding TE performanceis probably ascribed to the multiple interface structure of the PANI composite generated from incomplete dedoping and redoping processes, contributing to the enhanced carrier-filtering effect to retain a relatively high Seebeck coefficient and efficient charge transport to improve conductivity. Furthermore, the flexible TE device generates a high power of 1.5 mu W at Delta T = 50 K, demonstrating the applicability of this composite for energy-harvesting electronic devices.

Automated summary

By sequentially dedoping and redoping, the interface structure of carbon nanotubes/polyaniline composite films can be effectively regulated to enhance their thermoelectric properties. This leads to improved electrical conductivity, maintained Seebeck coefficient, and significantly higher power factor, making it suitable for energy-harvesting electronic devices.