Graphene Oxides for Homogeneous Dispersion of Carbon Nanotubes

Abstract

Graphene oxides (GOs) in terms of both structure and property are essentially polyelectrolytes in a two-dimensional sheet configuration. As is well-established in the literature, polyelectrolytes are, in general, good dispersion agents for single-walled carbon nanotubes (SWNTs), which are otherwise in bundles because of strong van der Waals interactions. We report here a study in which GOs were used to disperse SWNTs, both as-purified and separated semiconducting SWNTs, for solution-like homogeneous suspensions. As a demonstration for their potentials, the optically transparent dispersions were used in a more accurate determination of the absorptivities for the band-gap transitions in semiconducting SWNTs. Results on exploration of the use of the GO-dispersed SWNTs in the development of unique carbon nanocomposite materials are also presented and discussed.

Facile synthesis of reduced graphene oxide/MWNTs nanocomposite supercapacitor materials tested as electrophoretically deposited films on glassy carbon electrodes

“…MWNTs show a narrower D band, which may be due to the higher ordered structure of nanotubes compared with the fragmented GO. The 2D band of GO/MWNTs and LAA-rGO/MWNTs composites is attributed to the MWNTs, as there is no absorption for GO at the high excitation wavelength [12]. In addition, the D and G band peak shapes of GO/MWNTs and LAA-rGO/MWNTs were dominated by MWNTs, as evidenced by the narrower D band peak compared to GO and LAA-rGO, and similar G band peak shape to MWNTs [12].…”

“…The 2D band of GO/MWNTs and LAA-rGO/MWNTs composites is attributed to the MWNTs, as there is no absorption for GO at the high excitation wavelength [12]. In addition, the D and G band peak shapes of GO/MWNTs and LAA-rGO/MWNTs were dominated by MWNTs, as evidenced by the narrower D band peak compared to GO and LAA-rGO, and similar G band peak shape to MWNTs [12]. However, the G band peaks of GO/MWNTs and LAA-rGO/MWNTs at all conditions seem to show splitting into two peaks due to the presence of two species; i.e., GO and MWNTs or rGO and MWNTs.…”

“…Tian reported that graphene oxide can be used as a dispersing agent for single-walled carbon nanotubes (SWNTs) [12] whilst Zhang used graphene oxide to assist in the aqueous dispersion of multiwalled carbon nanotubes (MWNTs) [13]. Others have prepared hybrid graphene/carbon nanotube structures using hydrazine; a highly toxic chemical and a strong reducing agent [14].…”

Production of highly electro-conductive cellulosic paper via surface coating of carbon nanotube/graphene oxide nanocomposites using nanocrystalline cellulose as a binder

“…As a matter of fact, surface modification can impair their inherently unique properties, thus affecting the end-use performance, although the aqueous dispersion was greatly improved (Zhang et al 2010). Fortunately, graphene oxide (GO) used as a novel dispersant in aqueous system may solve the above mentioned problem (Tian et al 2010). GO, a two-dimensional (2D) and one-atomic-thick sp 2 carbon layer exfoliated from graphite, shares many similar properties to CNTs ).…”

Application of GO in Energy Conversion and Storage

“…To solve the issue of intrinsic insolubility of CNTs in water, GO with high solubility has been introduced as surfactant to disperse CNTs through strong π-π stacking interaction [165][166][167]. Dong et al [157] have experimentally demonstrated the spontaneous formation of SWCNT/ GO core-shell structure.…”