Polyaniline-nanocomposite based quad-layers thin film thermoelectric generator with enhanced power factor

This study introduces a quad-layer composite thermoelectric generator (TEG) film consisting of PANI-CSA/PEDOT:PSS-rGO/PANI-CSA/PEDOT:PSS-SWCNT. Unlike previous single- or bilayer systems, this quad-layer organic nanocomposite thin film integrates polyaniline (PANI) and PEDOT:PSS matrices with single-walled carbon nanotubes (SWCNTs) and reduced graphene oxide (rGO) nanofillers. After optimizing the parameters of each layer, a prototype TEG device was fabricated with four legs of the quad-layer film on a flexible Kapton substrate. At room temperature (ΔT ≈ 30 K), the device exhibited a Seebeck coefficient of 199.56 μV·K⁻¹ and an electrical conductivity of 5384 S·m⁻¹ . Consequently, the power factor (PF) reached 214 μW·m⁻¹ ·K⁻². The improved performance results from energy filtering at the polymer–nanocomposite interfaces and efficient charge transport through SWCNTs and rGO sheets. These mechanisms enhance both the Seebeck coefficient and power factor. Device-level evaluation of the flexible four-leg TEG yielded a peak output voltage of 5987 μV and an efficiency of 0.47 % at ΔT = 30 K, confirming proof-of-concept operation. The thermal conductivity of the multilayer structure was determined using a series thermal resistance model, which enabled calculation of power output, figure of merit, and maximum conversion efficiency. These findings suggest that multilayered organic composites with synergistic filler combinations and engineered interfaces are promising candidates for efficient thermoelectric applications. This method offers a cost-effective and scalable approach for energy harvesting, particularly in the recovery of low-grade waste heat. Although the device-level efficiency is currently modest, the quad-layer architecture offers essential insights and establishes a basis for developing flexible, low-cost thermoelectric generators.