Fermi-Level Dependence of the Chemical Functionalization of Graphene with Benzoyl Peroxide

The dependence of the chemical functionalization of graphene on its Fermi level was investigated based on a heat-initiated solid-phase chemical reaction with benzoyl peroxide. The chemical functionalization was performed during application of a gate voltage to shift the Fermi level. A gate-voltage-induced variation of the reactant concentration on the graphene surface could not occur because of the neutral intermediate and the solid-phase reaction. Raman measurements on functionalized graphene showed that a higher Fermi level led to more reacted carbon atoms, which was interpreted in terms of the energy-level alignment between graphene and phenyl radical.