Modification of graphene with two strong acids and its nanocomposites with 2-hydroxyethylcellulose

Abstract

Simple and cost-effective, eco-friendly, graphene-based “green” nanocomposite films are produced with the solvent casting method. For this purpose, commercially procured nanographene was used as reinforcement material and 2-hydroxyethyl cellulose (2-HEC), a cellulose-derivative natural polymer, was used as a matrix. Nanographene was modified with HCl and HNO3 to ensure blending with the cellulose matrix, and 2-HEC/acid modified graphene nanocomposite films were produced. The results show that the basic structure of the graphene is preserved after the HCl and HNO3 modifications. FT-IR, XRD, and Raman Spectroscopy results show that the graphene attained hydrophilic property by creating functional ends (hydroxyl group, –OH) on the edges of the graphene sheet with acid modification. Morphology studies with SEM and AFM methods have also confirmed the acid modification to the graphene. TGA/DTG work revealed that nanocomposite films obtained as a result of the doping of HNO3 modified graphene to the 2-HEC matrix were found to be thermally more stable than the original 2-HEC film. In this study, where 2-HEC is used as a matrix, the hydrophilic property has been achieved with the hydrophobic graphene by acid modification. The resulting 2-HEC/acid modified graphene nanocomposite materials have the potential to lead to innovation in applications such as lithium-ion batteries and sensor design, water treatment and even drug delivery systems.