Diels-Alder reactions of graphene: computational predictions of products and sites of reaction

Repurposing of oxazolone chemistry: gaining access to functionalized graphene nanosheets in a top-down approach from graphite

Solvent-free 1,3-dipolar cycloaddition reactions of graphite flakes and mesoionic oxazolones lead to the direct functionalization and delamination of graphite flakes into few layers of graphene nanosheets.

Solvent-free 1,3-dipolar cycloaddition (1,3-DC) reactions between graphite flakes and mesoionic oxazolones were carried out by heating the resulting solid mixture at mild temperatures (70–120 °C). The direct functionalization and delamination of graphite flakes into few layers of graphene nanosheets was confirmed by micro-Raman and X-ray photoelectron spectroscopies, scanning transmission electron microscopy and thermogravimetric analysis. The 1,3-DC reactions of mesoionic dipoles have been investigated with density functional theory to model graphene, exploring three different pathways: center, corner and edge. These theoretical calculations highlighted that the 1,3-DC reaction can proceed both through a concerted mechanism competing with a stepwise one involving a zwitterionic intermediate. The irreversible decarboxylation inherent in the last step justifies the high degree of functionalization experimentally observed, representing the driving force of the process.

Reactivity of Fluorographene: A Facile Way toward Graphene Derivatives

Fluorographene (FG) is a two-dimensional graphene derivative with promising application potential; however, its reactivity is not understood. We have systematically explored its reactivity in vacuum and polar environments. The C-F bond dissociation energies for homo- and heterolytic cleavage are above 100 kcal/mol, but the barrier of SN2 substitution is significantly lower. For example, the experimentally determined activation barrier of the FG reaction with NaOH in acetone equals 14 ± 5 kcal/mol. The considerable reactivity of FG indicates that it is a viable precursor for the synthesis of graphene derivatives and cannot be regarded as a chemical counterpart of Teflon.

High-yield production of highly conductive graphene via reversible covalent chemistry

A reversible covalent strategy based on the Diels–Alder reaction of graphite and tetracyanoethylene has been developed for the high-yield production of high-quality few-layer graphene.

Chemical nature of boron and nitrogen dopant atoms in graphene strongly influences its electronic properties

The electronic properties of the N- and B-doped graphenes depend, besides the doping element, on the nature of doping.

A solvent-free Diels–Alder reaction of graphite into functionalized graphene nanosheets

A solvent-free Diels–Alder reaction between graphite as a diene and a typical dienophile, maleic anhydride or maleimide is developed. The functionalization of graphite with dienophiles is efficient enough for delamination of graphitic layers into graphene nanosheets upon dispersion in a polar solvent.