Solutions of fully exfoliated individual graphene flakes in low boiling point solvents

Abstract

6 pagesInternational audienceGraphenide solutions (solutions of negatively charged graphene flakes) have been prepared in low boiling point solvents such as tetrahydrofuran (THF) by dissolution of the graphite intercalation compound (GIC) KC8. The presence of two-dimensional objects in solution, with an average lateral size of over one micron, is evidenced by light scattering analysis. High resolution transmission electron microscopy analysis shows that the solubilized graphene flakes are exclusively single and double layers with no evidence for thicker species. Molecular dynamics simulations support the graphene folding, observed in TEM, and suggest it is triggered by solvent nanodrops

Thermal Decomposition of Ternary Sodium Graphite Intercalation Compounds

“…Reductive dissolution of nanocarbons is a versatile and widely used methodology to achieve individualisation, exfoliation and functionalisation of carbon nanotubes (CNTs), fullerenes, and other graphitic nanomaterials; it has been extended, more recently, to graphene analogues, such as carbon nitride and transition‐metal dichalcogenides . For the exfoliation of graphite in particular, graphite intercalation compounds (GICs) are a convenient precursor to obtaining “graphenide” solutions in various solvents, such as tetrahydrofuran (THF) and N ‐methylpyrrolidone (NMP) . Alkali metal GICs have long been studied, but with the sudden growth in graphene research since 2004, there has been renewed interest in GICs as a possible route to obtaining isolated single‐layer graphene, as well as covalently modified graphene derivatives.…”

Bottom-up and top-down manipulations for multi-order photonic crystallinity in a graphene-oxide colloid

“…5 Structural coloration has also been demonstrated in other colloidal systems such as in the swollen lamellar mesophase of plate-like particles with or without a supporting polymer network or surfactants, [6][7][8] the columnar phase of regularly sized plate-like particles [8][9][10] and the steric packing assembly of silica or polymer spheres or cubes. [11][12][13] Nonetheless, color reflection in the GO dispersion is quite unexpected, considering that GO particles are highly polydisperse, irregularly shaped, curved in solution, 14,15 and two orders of magnitude thinner than the photonic band-gap. From a practical point of view, photonic crystals potentially allow the use of GO in various optical applications, as long as an easy method is provided for manipulation.…”

Solubilization of Fullerenes, Carbon Nanotubes, and Graphene

“…Although a detailed analysis like the one that has been performed on nanotubes [31] has not been attempted, by analogy it is expected that both the entropy gain with counterions dissolution and a rather favorable graphenide-solvent interaction lead to these thermodynamically stable solutions. Graphenides have been shown to be individualized in solution [91,95]. Absorption spectra in NMP show a strong peak at 300 nm (4.1 eV), characteristic of negatively charged graphene sheets (Fig.…”

“…Graphenide solutions are prepared by exposure to a suitable solvent such as NMP [89,94], THF [91,95], or 1,2-dimethoxyethane (DME) [92], of a graphite intercalation compound (Fig. 22).…”