Interfacial Interactions of Single-Walled Carbon Nanotube/Conjugated Block Copolymer Hybrids for Flexible Transparent Conductive Films

Abstract

Nanohybrids consisting of single-walled carbon nanotubes (SWCNTs) and a conductive block copolymer, perchlorate-doped poly(3,4-ethylenedioxythiophene)-block-poly(ethyleneoxide) (P-PEDOT-b-PEO), were successfully prepared. Individual exfoliation of SWCNTs and high solution processability were simultaneously achieved in the supramolecular assembly. The assembly at the molecular level was driven by the interfacial interaction between SWCNT walls and the PEDOT block, as characterized by various spectroscopic analyses (UV-Vis, FT-IR, PL, and Raman). The exfoliation of SWCNTs and the solubility of the nanohybrids, which are facilitated by the soluble PEO block, were confirmed by Raman spectroscopy and a range of other microscopy techniques (AFM, TEM, and SEM). Flexible transparent conductive films of the nanohybrids were fabricated using a vacuum-assisted filtration method. The films displayed high electrical conductivity with good mechanical integrity due to the strong interaction between the SWCNT and the conductive polymer. The strategy described here opens up promising possibilities for the fabrication of CNT/conjugated polymer hybrids as well as for their use in flexible electronics.