Structure and Interaction of Graphene Oxide– Cetyltrimethylammonium Bromide Complexation

Abstract

Complexation of graphene oxide (GO) and cetyltrimethylammonium bromide (CTAB), a model amphiphile, was quantitatively studied to elucidate the governing forces and resulting structures of their self-assembly. We systematically varied pertinent self-assembly parameters, including GO size, mixing ratio, salt, and osmotic stress, and quantified the nanoscale structures of GO:CTAB using x-ray diffraction (XRD). Multilamellar stacking of GO and CTAB layers persists in all GO:CTAB assemblies exhibiting structural order. While driven by hydrophobic interactions between the hydrocarbon tails, the CTAB layer displays a series of structural transitions from a bilayer with in-plane ordering to a more fluidic bilayer and to an interdigitated monolayer. Interaction between GO and CTAB layers shows to be dominated by electrostatics, and osmotic stress studies indicate the absence of continuous hydration layers in GO:CTAB assemblies. Adding salt increases the inter-layer spacing by intercalating between GO and CTAB layers, and this ion layer can be expelled by high osmotic stress. These studies provide quantitative knowledge of the structure and interaction of GO:CTAB complexation, which lays foundation for precise control and rational design of their nanoscale self-assemblies.

Cation-diffusion controlled formation of thin graphene oxide composite membranes for efficient ethanol dehydration

“…The pioneering work on unimpeded water transport through graphene-based membrane [11] has elicited a bunch of interesting experiments [12][13][14] and simulations [15][16][17] to study the fast-selective mass transfer through GO-based laminates. From nano-sized particles (e.g., carbon dots [18]), small molecules (e.g., piperazine [19], surfactant [20,21]) to polymer chains (e.g., polyvinyl alcohol [22]), different chemical species are manipulated to modulate nanostructures and properties of GO-based membranes. With the methodology to functionalize GObased materials, several kinds of membranes for separating specific mixtures [23][24][25][26][27][28][29][30] have been developed.…”

Preparation of gemini surfactant/graphene oxide composites and their superior performance for Congo red adsorption

“…21 Notably, GO-based composites modied by surfactants have recently attracted signicant attention because of the easy availability and high efficiency of surfactants. [22][23][24] Liang et al 25 reported for the rst time that cationic surfactants were used to modify GO by ionic interactions, thereby reducing the hydrophilicity of the graphene composites. Subsequently, Yusuf and coworkers prepared a graphene composite intercalated with cetyltrimethylammonium bromide (CTAB), and the obtained composite showed great removal capacity for organic dyes and good recovery.…”

The Influence of the Interlayer Distance on the Performance of Thermally Reduced Graphene Oxide Supercapacitors

“…The hydrophobic nature of the graphene would lead to the quick aggregation of the RGO sheets; the RGO sheets would thus lose their attraction as individual objects and further processing of the composite materials would be hindered [ 3 ]. The use of surfactants is common to keep the suspension stabilized in solution while preventing the restack of the RGO sheets in solid [ 11 , 12 , 13 ]. Ionic surfactants are amphiphilic compounds made up of ionic hydrophilic head groups and extended apolar, organic residues and hydrophobic tails.…”