A Facile Method for Synthesis of Uniform Size and Well Dispersed Reduced Graphene Oxide Solutions and Graphene Powder

摘要

In present study, a simple two-step process consisting of electrochemical exfoliation coupled with ultrasonication assisted solvent homogenization technique is demonstrated for continuous and direct synthesis of well dispersed, highly concentrated and uniform size reduced graphene oxide (RGO) solutions in different solvent media. About 92 wt% RGO solution （concentration ≈11 mg/ml） was obtained in sulfuric acid in the first step whereas about 31 wt% RGO solution (concentration ≈14 mg/ml） in the second step. Using present two stage process, remarkably around 99% of exfoliated graphite can be converted to RGO. For the first time a simple 3D-surface profiling system has been introduced for dimensional analysis of RGO particle. Raman and thermogravimetric analysis were carried out to confirm and correlate the differential dispersion behavior of synthesized RGO in different solvents. The possibility of low temperature reduction of RGO to graphene without using any chemical has been presented with in-situ X-ray diffraction studies.