Facile synthesis of graphene oxide in a Couette-Taylor flow reactor

A practical approach to bulk-scale graphene-based materials is critically important for their use in the industrial applications. Here, we describe a facile method to prepare graphite oxide (GO) using a Couette-Taylor flow reactor for the oxidation of bulk graphite flakes. We found that the turbulent Couette-Taylor flow in the reactor could be engineered to result in the efficient mixing and mass transfer of graphite and oxidizing agents (KMnO₄ and H₂SO₄), thereby improving the efficiency of graphite into GO. As compared to the standard Hummers' method, higher fraction of a single- and few-layer graphene oxide (G-O) can be yielded in a dramatically shortened reaction time, by optimizing the processing parameters, we have shown that ∼93% of G-O yield could be achieved within 60 min of reaction time. This method also allowed for the in-situ functionalization of G-O with metal oxide nanoparticles to give a nanoparticle-decorated G-O hybrid material. Our method for facile and large-scale production of graphite oxide may find utility in a range of applications including energy storage, composites and supporting frameworks of catalyst.