Two-dimensional (2D) conducting polymers are expected to offer emergent topological, structural, and physical properties, which has become the "holy grail" for the development of plastic electronics. Here, we report the assembly of a free-floating metallic polymer layer, consisting of poly(3,4-ethylenedioxythiophene) complexed with poly(styrenesulfonate) anions, directed by electrostatic recognition, amphiphilicity, and aromatic interactions. The obtained large-area crystalline nanosheets exhibit excellent environmental stability and mechanical robustness, meanwhile showing an electrical conductivity of 1216 S·cm-1, the highest among the nanometer-thick conducting polymers. The kirigami-inspired freestanding polymer thermoelectrics, repeatedly stretching up to 200% strain, is demonstrated with high Seebeck coefficient with an optimized power factor of 95 μW m-1 K-2. The large-scale assembly and aqueous compatibility of 2D conducting polymers provide an exciting platform for integrating thermoelectricity into free-floating polymer nanostructures.
Keywords: freestanding; kirigami; polymer nanosheet; self-assembly; thermoelectrics.