Hydroboration of graphene oxide: Towards stoichiometric graphol and hydroxygraphane

Covalently functionalized graphene materials with well-defined stoichiometric composition are of a very high importance in the research of 2D carbon material family due to their well-defined properties. Unfortunately, most of the contemporary graphene-functionalized materials do not have this kind of defined composition and, usually, the amount of heteroatoms bonded to graphene framework is in the range of 1-10 at.-%. Herein, we show that by a well-established hydroboration reaction chain, which introduces -BH₂ groups into the graphene oxide structure, followed by H₂O₂ or CF₃COOH treatment as source of -OH or -H, we can obtain highly hydroxylated compounds of precisely defined composition with a general formula (C₁O_0.78H_0.75)_n, which we named graphol and highly hydroxylated graphane (C₁(OH)_0.51H_0.14)_n, respectively. These highly functionalized materials with an accurately defined composition are highly important for the field of graphene derivatives. The enhanced electrochemical performance towards important biomarkers as well as hydrogen evolution reaction is demonstrated. Stand out from the crowd: By using a well-established hydroboration reaction chain it is possible to obtain highly hydroxylated compounds of precisely defined composition with a general formula (C₁O_0.78H_0.75)_n, named graphol and highly hydroxylated graphane (C₁(OH)_0.51H_0.14)_n (see figure). Compared with graphene, the compounds demonstrate enhanced electrochemical performance.