(639j) Interface Optimization and Thermoelectric Application of Polyaniline/CNT

Energy is fundamentally needed for all human activities. However, the low consumption efficiency, where approximately 70% of the total energy produced by humanity dissipates as waste heat, further exacerbates the energy crisis and global warming. The thermoelectric generator is a promising approach to recover this low-grade energy. Especially, polymer thermoelectric materials have drawn much attention due to their flexibility, processability, and inexpensiveness. Polyaniline, as one of the most commonly used conjugated polymers, could form π-π interaction with carbon nanotubes resulting from the aromatic structure on its backbone. This interaction would contribute to high-quality interface formation, which introduces an energy filtering effect that balances electrical conductivity and the Seebeck coefficient, as well as the phonon scattering effect that suppresses thermal conductivity in our research. Hydrogen bonds were further introduced via functionalized carbon nanotube to improve the local alignment of polyaniline. With an enhanced figure of merit, multi-phase thermoelectric films were coated, and thermoelectric modules were assembled to verify the scalability. This research highlighted the importance of microscopic interface design between polymer and carbon nanotube to the macroscopic thermoelectric properties, and shed light on the application of conjugated polymers to practical thermoelectric usage.