High-Performance Stretchable Thermoelectric Multilayers Enabled by a Synergistic Elastomer-Conjugated Network

Abstract

The development of wearable electronics is critically dependent on the creation of power sources that are not only efficient but also mechanically compliant to withstand the dynamic movements of the human body. This work introduces a novel, water-based layer-bylayer (LbL) assembly of a PPy:NPs/DWNT-PEDOT:PSS/PEO/PAA quadlayer (QL) nanocomposite designed to address this challenge. The architecture comprises an alternating sequence of a high-performance thermoelectric (TE) bilayer (BL), consisting of cationic polypyrrole nanoparticles (PPy:NPs) and an anionic dispersion of double-walled carbon nanotubes stabilized with poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (DWNT-PEDOT:PSS), and an elastomeric BL of polyethylene oxide (PEO) and poly(acrylic acid) (PAA). The 20 BL PPy:NPs/DWNT-PEDOT:PSS thin films exhibit a high power factor of 183.3 μW m -1 K -2 , driven by a desirable decoupling of electrical conductivity and Seebeck coefficient, a phenomenon attributed to interfacial energy filtering effects inherent to the nanostructured assembly. Incorporation of elastomeric PEO/PAA layers yields crack-free QL films that sustain up to 30 % strain while maintaining ~88 % of the initial Seebeck coefficient, with only modest resistance changes. Remarkably, the TE properties decrease by less than 11 % after 1000 bending and twisting cycles, underscoring the superior durability of the multilayers.