Photochemical Reactivity of Graphene

We demonstrate a photochemical reaction between graphene and benzoyl, peroxide. This reaction introduces spatially localized defects into the graphene basal plane. The reactivity of the single-layer graphene is similar to 14 times higher than that of the double-layer graphene. Our result suggests that photoexcited graphene transfers a hot electron to benzoyl peroxide and induces its decomposition to a phenyl radical.