Simultaneous Reduction and Functionalization of Graphene Oxide by 4-Hydrazinobenzenesulfonic Acid for Polymer Nanocomposites

Abstract

Graphene oxide (GO) was functionalized and reduced simultaneously by a new reductant, 4-hydrazinobenzenesulfonic acid (HBS), with a one-step and environmentally friendly process. The hydrophilic sulfonic acid group in HBS was grafted onto the surface of GO through a covalent bond. The successful preparation of HBS reduced GO (HBS-rGO) was testified by scanning electron microscope (SEM), X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectra (FTIR), X-ray photoelectron spectroscopic (XPS) and thermogravimetric analysis (TGA). The interlayer space of HBS-rGO was increased to 1.478 nm from 0.751 nm for GO, resulting in a subdued Van der Waals’ force between layers and less possibility to form aggregations. The aqueous dispersibility of graphene was improved to 13.49 mg/mL from 0.58 mg/mL after the functionalization. The viscosity of the epoxy resin based HBS-rGO composite could be regulated by an adjustment of the content of HBS-rGO. This study provides a new and applicable approach for the preparation of hydrophilic functionalized graphene, and makes it possible for the application of graphene in some functional polymer nanocomposites, such as specialty water-based coatings.

Stepwise Reduction of Graphene Oxide (GO) and Its Effects on Chemical and Colloidal Properties

“…1 . In line with what has been reported before, the GO sheets had smooth surface while the r-GOs showed folded regimes and wrinkles 37 .…”

Simultaneous reduction and surface functionalization of graphene oxide for highly conductive and water dispersible graphene derivatives

“…3c). The successful reduction of GO is further indicated by the removal of the epoxy peak at 1053 cm −1 while the presence of the sulfonic groups is confirmed by the appearance of the intense peaks at 1165 (deformation vibration for S=O) [49,50,55,56] and 1030 cm −1 (shoulder, symmetric vibration of O=S=O group) [56,57] in agreement with the X-ray photoelectron spectroscopy results (shown below). Thus, the spectra show clearly that the sulfonated aromatic diamines are present in the reduced GO sheets.…”

“…The spectrum of GO is very similar to those already reported [15,46]. Τhus, the strong and broad peak at ~ 3428 cm −1 is due to the stretching vibrations of O-H bond (carboxylic) [17,46,47], the shoulder at 1700 cm −1 to C=O stretching vibrations in carboxylic and carbonyl moieties presented at the edges of the GO sheets and at the edges of holes [17,[46][47][48][49], the peaks at 1623 cm −1 and 1400 cm −1 are allocated to C=C in aromatic rings [46,49,50] and to the deformation vibrations of carboxylic O-H groups [17,48]. The peak at 1220 cm −1 is usually assigned to phenolic C-OH vibration [48,51] and that of 1053 cm −1 is assigned to the epoxy (or alcoxy) vibration [52][53][54].…”

Anomalous Charge‐Extraction Behavior for Graphene‐Oxide (GO) and Reduced Graphene‐Oxide (rGO) Films as Efficient p‐Contact Layers for High‐Performance Perovskite Solar Cells

“…[22] The intensities of infrared absorption of the CO and CO functional groups decreased upon reduction of GO into rGO-NH and rGO-BH. [24] Further details about the extent of reduction of GO sheets were deduced from XPS of the C1s core level; the characteristic XPS signals shown in Scheme 1 were deconvoluted into four components, which are attributed to the trigonally coordinated carbons in CC, CO, CO, and OCO groups, respectively. This negative dipolar moment causes a stable aqueous suspension and might generate a uniform film with satisfactory conductivity.…”