Flexible, Freestanding Ternary Nanocomposite Thick Film of Polyaniline/WS₂/CNTs for Efficient Thermoelectric Application

Conducting polymers are promising for near-room-temperature, wearable thermoelectric applications due to their flexibility, inherently low thermal conductivities, and tunable electrical conductivities. This work reports the fabrication of a flexible nanocomposite thick film consisting of conducting polymer, polyaniline (PANI), WS 2 nanosheets, and carbon nanotubes (CNTs) and investigates its thermoelectric properties. The incorporation of WS 2 nanosheets results in an ∼3 times enhancement in the Seebeck coefficient because of the high Seebeck coefficient of WS 2 nanosheets and the energy filtering effect at the PANI–WS 2 interface. The incorporation of CNTs acts as a conducting filler in the PANI/WS 2 matrix, which helps in improving the mobility of charge carriers and enhances the electrical conductivity. Hence, the simultaneous incorporation of WS 2 nanosheets and CNTs synergistically increases the Seebeck coefficient and the electrical conductivity in the nanocomposite thick films, which results in an ∼13 times enhancement in the power factor and an ∼10 times enhancement in the figure of merit (zT) at room temperature in comparison to pristine PANI film. The study suggests that the simultaneous incorporation of WS 2 nanosheets and CNTs in PANI is a promising strategy to improve the thermoelectric properties of PANI-based materials.