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

Composite nanocoating of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) and aqueous dispersion of carbon nanotubes (CNT-PSS) on lignocellulose wood microfibers has been developed to make conductive micro fibers and paper sheets. To construct the multilayers on wood microfibers, cationic poly(ethyleneimine) (PEl) has been used in alternate deposition with anionic conductive PEDOT-PSS and solubilized CNT-PSS. Using aKeithley microprobe measurement system, current-voltage measurements have been carried out on single composite microfibers after deposition of each layer to optimize the electrical properties of the coated microfibers. The conductivity of the resultant wood micro fibers was in the range of 10^2 -2 S cm^-1 depending on the architecture of the coated layer. Further, the conductivity of the coated wood rnicrofibers increased up to 20 S cm^-1 by sandwiching multilayers of conductive co-polymer PEDOT-PSS with CNT-PSS through a polycation (PEl)interlayer. Moreover, paper hand sheets were manufactured from these coated wood micro fibers with conductivity ranging from 1 to 20 S cm^-1. A paper composite structure consisting fconductive/dielectric/conductive layers that acts as a capacitor has also been fabricated and isreported.