Conductive paper from lignocellulose wood microfibers coated with a nanocomposite ofcarbon nanotubes and conductive polymers

Abstract

Composite nanocoating of poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate)(PEDOT–PSS) and aqueous dispersion of carbon nanotubes (CNT–PSS) on lignocellulosewood microfibers has been developed to make conductive microfibers and paper sheets.To construct the multilayers on wood microfibers, cationic poly(ethyleneimine)(PEI) has been used in alternate deposition with anionic conductive PEDOT–PSSand solubilized CNT–PSS. Using a Keithley microprobe measurement system,current–voltage measurements have been carried out on single composite microfibersafter deposition of each layer to optimize the electrical properties of the coatedmicrofibers. The conductivity of the resultant wood microfibers was in the range of10−2–2 S cm−1 dependingon the architecture of the coated layer. Further, the conductivity of the coated wood microfibers increasedup to 20 S cm−1 by sandwiching multilayers of conductive co-polymer PEDOT–PSS with CNT–PSSthrough a polycation (PEI) interlayer. Moreover, paper hand sheets weremanufactured from these coated wood microfibers with conductivity ranging from 1 to20 S cm−1. A paper composite structure consisting of conductive/dielectric/conductive layers thatacts as a capacitor has also been fabricated and is reported.