Graphite exfoliation in cellulose solutions

Abstract

Shaking graphite powder dispersed in an aqueous alkaline cellulose solution produces stable dispersions of hydrophilic, thin graphite sheets with lateral dimensions reaching many micrometers. The X-ray diffractogram and Raman spectrum of the exfoliated graphite differ from the well-known graphite patterns. Analytical transmission electron micrographs show cellulose bound to the surface of thin lamellae and this is confirmed by scanning probe micrographs. The dispersant properties of dissolved cellulose are assigned to its adsorption on graphite by juxtaposition of the hydrophobic planes on both substances, forming hydrophilic particles. This method uses only simple and easily accessible chemicals, processed under mild conditions. The resulting nanographite-cellulose dispersions are suitable for making conductive lignocellulosic nanocomposites and coatings.