Solution-phase Graphene Synthesis

Graphene, as the perfect assembly of carbon atoms, has remained central to materials research since its discovery. Chemical synthesis of graphene from molecular precursors in solution represents a longstanding challenge for chemists. Building graphene crystals from small-molecule carbon sources requires reversible C–C coupling, chain extension, and aromatization with error self-correction through dynamic covalent chemistry, theses processes are considered fundamentally impossible under mild solution-phase conditions. Here we report a one-pot solution-phase method that directly transforms chemically inert C(sp3) solvents (CH2Cl2, CHCl3 or CCl4) into graphene. This carbocation-mediated transformation is enabled by a “super magic acid” combining CF3SO3H with Hg(OTf)2 that exhibits extraordinary proton catalysis, achieving over 10^14 C–C coupling events with ordered aromatization, ultimately producing single-crystal graphene exceeding 50 μm × 50 μm × 1 μm with clearly visualized Dirac cones. Butylated hydroxytoluene (BHT) was isolated as a key intermediate, representing the first abiotic C(sp3) small molecular to aromatic structure conversion in wet chemistry. Beyond graphene synthesis itself, this work demonstrates that our novel super magic acid-enabled reversible carbocation chemistry can overcome kinetic barriers previously requiring extreme conditions. This principle has broader implications for solution-phase assembly of aromatic materials and challenging C–C bond formations.