Gram‐Scale Bottom‐Up Synthesis of Macrographene

Abstract

Herein we report a very facile, bottom‐up synthesis of macrographene sheets of up to 1–2 μm size, in two steps from readily available starting materials under mild reaction conditions. The synthesis involved the reduction of 4,4’‐biphenylene bisdiazonium salt in aqueous solution at room temperature using methanolic sodium borohydride. The reduction reaction results in the formation of 4,4’‐biphenylele biradicals which underwent rapid addition reactions to give a cross‐linked polycyclic aromatic hydrocarbon frame work. Scholl oxidation of the aromatic frame work gave macrographene sheets in good yields in gram quantities. Formation of the graphene sheets was confirmed by several technique including X‐ray photoelectron spectroscopy, Raman spectroscopy, TEM and AFM analysis.