A quantitative analysis of the dispersion behavior of reduced graphene oxide in solvents

Abstract

Detailed knowledge of the dispersion behavior of reduced graphene oxide (RGO) in solvents is important for its practical applications. Such behavior is expected to be different to that observed for pristine graphene, as a result of the chemically heterogeneous structure of RGO (patchwork of pristine and highly oxidized graphene domains). We have investigated the dispersibility of RGO in a wide range of solvents and analyzed the results on the basis of solvent surface energies and Hansen solubility parameters. Although RGO exhibited some features that are characteristic of pristine graphene, its dispersion behavior was dominated by its oxidized graphene domains, with alcohols being commonly the most successful solvents. Estimates of the effective Hansen parameters for RGO derived from the experimental data ( D ≈ 16.9 MPa 1/2 ,  P ≈ 10.7 MPa 1/2 and  H ≈ 14.1 MPa 1/2) were consistent with this view and afforded the rational design of solvent mixtures that surpassed the best single-component solvents in terms of dispersed amount of RGO. RGO-polymer composites could then be readily prepared in the best performing solvents. Overall, the present results provide a guide to the processing of RGO in the liquid phase with practical utility in the preparation of different graphene-based materials.

High-efficient Synthesis of Graphene Oxide Based on Improved Hummers Method

“…The G-band reflects the first order scattering of E 2g phonon of graphitic carbon, while D-band (1360 cm −1 ) relates to the formation of defects and disorder2536, such as grain boundaries, hetero-atoms introduced in graphene planes, etc. In fact, GO sheet consists of two kinds of domains37: graphitic domains inherited from their parent graphite and highly oxidized domains due to oxidation. Therefore, D-band mainly records the information of GO distinct from graphite, especially the oxidation-induced defects and disorder, and the intensity ratio of D-band to G-band, I D /I G , indirectly reflects the oxidation degree243839.…”

Fabrication of Au/GO/ZnO composite nanostructures with excellent photocatalytic performance

“…2a shows the UVevis absorption spectra of colloidal GO, Au, and Au/GO hybrid. A peak at 230 nm and a shoulder at 295 nm signify the formation of GO [27]. A peak at about 520 nm is attributed to the surface plasmon resonance peak of Au NPs [28].…”

A biofunctionalizable ink platform composed of catechol-modified chitosan and reduced graphene oxide/platinum nanocomposite

“…Briefly, 2 g/L, 5 g/L, and 10 g/L of rGO–Pt was dispersed in EG via bath sonication (8 h, Polsonic Sonic-10, 40 kHz), followed by centrifugation (1 h, MPW 223e, 2500 RCF), another round of sonication (1 h), and finally another round of centrifugation. Dispersion concentrations were assessed via UV–vis spectrophotometry [21]. Transmission electron microscopy (TEM) (FEI Tecnai F30, Frequency Electronics Inc.) was employed to examine the morphology of the samples and confirm that the dispersion process did not remove Pt nanoparticles from rGO–Pt.…”