The cross-interface energy-filtering effect at organic/inorganic interfaces balances the trade-off between thermopower and conductivity

Abstract

A cooperative 3D carrier transport mode including the 1D metallic transport along the paracrystalline PANI and the 2D cross-interface energy-filtering transport balances the trade-off between thermopower and conductivity.

All-Solution-Processed Polythiophene/Carbon Nanotube Nanocomposites Integrated on Biocompatible Silk Fibroin Substrates for Wearable Thermoelectric Generators

“…Carbon allotrope-based thermoelectric materials, particularly carbon nanotubes (CNTs), are generally characterized by good electrical properties, high thermal stability, and high thermal conductivity. − Therefore, tunable amounts of carbon-based nanofillers are usually added to conducting polymer nanocomposites to improve their electrical charge transport and thermoelectrical properties. − The interfaces between nanofillers and conjugated polymers in the nanocomposites can form a specific charge-carrier pathway, resulting in an energy-filtering effect that enhances the Seebeck coefficient ( S ) without compromising the electrical conductivity (σ). − Although CNTs have excellent σ that can compensate for the low σ of polymer matrices, the adequate dispersion of CNTs within nanocomposites is still an essential issue for conducting solution processing and achieving large-area and high-throughput thermoelectric devices. This difficulty in dispersing CNTs is overcome by introducing the surfactant or conjugated polymers through intermolecular interactions between CNTs and polymers. − However, using vacuum filtration for bulk or film thermoelectric nanocomposites is a poor strategy since free-standing thermoelectric nanocomposites need to be cut and interconnected by conducting electrodes for the module to be used .…”

Tunable Thermoelectric Performance of the Nanocomposites Formed by Diketopyrrolopyrrole/Isoindigo-Based Donor–Acceptor Random Conjugated Copolymers and Carbon Nanotubes

“…Consequently, the PCDTPT/FWCNT composite films showed superior thermoelectric performances with an improved PF of up to 459 μW m –1 K –2 Figure S1 illustrates the progress made in enhancing PF values for donor–acceptor conjugated polymer/SWCNT nanocomposites, and Table summarizes the various processing methods used to prepare nanocomposite films and their thermoelectric performance. − However, few studies have investigated the carrier-filtering effect in nanocomposites consisting of low bandgap polymers. − Therefore, it is essential to develop D–A conjugated polymers with appropriate energy levels for use in thermoelectric nanocomposite systems in order to investigate the impact of efficient carrier filtering on thermoelectric properties.…”