Fabrication of High-Concentration and Stable Aqueous Suspensions of Graphene Nanosheets by Noncovalent Functionalization with Lignin and Cellulose Derivatives

Abstract

Stable aqueous suspensions of graphene (G) nanosheets with high concentration (0.6−2 mg/mL) were prepared through chemical reduction of exfoliated graphite oxide (EGO) with the aid of sodium lignosulfonate (SLS), sodium carboxymethyl cellulose (SCMC), and pyrene-containing hydroxypropyl cellulose (HPC-Py). The noncovalently functionalized graphene nanosheets with a 3.3 ± 1.4 nm average thickness were characterized with use of UV−vis spectroscopy, fluorescence spectroscopy, atomic force microscopy, attenuated total reflectance micro-Fourier transform infrared spectroscopy, and Raman spectroscopy.