Fabrication of exfoliated graphene nanomaterials from graphite and their applications

Abstract

Graphene nanomaterials are fabricated by chemical exfoliation from graphite. In particular, one-dimensional fibrous graphene oxide is obtained by ice-templating of graphene oxide solution, and is reduced by vapor phase reduction without any morphological changes. When the atmospheric Ar plasma is introduced to the one-dimensional graphene oxide, it is also possible to reduce the one-dimensional graphene oxide in less than 10 seconds without toxic reducing agents. The graphene model for dissipative particle dynamics is proposed by adding additional forces between graphene beads, and is calibrated by structural characteristics analysis. The self-assembly phenomenon between graphene model and surfactants in aqueous solution is analyzed by dissipative particle dynamics. The self-assembly phenomena of a graphene nanosheet in SDS surfactant solution is predicted, and diverse self-assemblies of graphene/surfactants are also predicted with concentration of surfactants. Graphene/copper(II) oxide nanocomposite is synthesized using exfoliated graphene oxide by aqueous-phase chemical method. The synthesized CuO had an urchin-like shape densely composed of nano-needles, and the synthesized nanocomposites presented excellent antibacterial performance against both Gram-positive and Gram-negative bacteria. In addition, graphene oxide solution is reduced without reducing agents by mechanical mixing with high speed. It is possible to reduce in diverse solvents, and the product shows high dispersion stability. Reduced graphene oxide solution based ethylene glycol is applied to nanofluids, and the thermal conductivity of the nanofluid with 1 wt% has increased 16.4% compared to that of base fluid.