MIT engineers have developed a continuous manufacturing process that produces long strips of high-quality graphene. The custom-built, roll-to-roll CVD system makes graphene on copper foil at 1,000 °C. The results, published in the American Chemical Society (ACS), are the first demonstration of an industrial, scalable method for manufacturing high-quality graphene that is tailored for use in membranes that filter a variety of molecules, including salts, proteins, or nanoparticles. These membranes should be useful for desalination, biological separation, and other applications.
A Scalable Route to Nanoporous Large-Area Atomically Thin Graphene Membranes by Roll-to-Roll Chemical Vapor Deposition and Polymer Support Casting, 19 Mar 2018.
Abstract: Scalable, cost-effective synthesis and integration of graphene is imperative to realize large-area applications such as nanoporous atomically thin membranes (NATMs). Here, we report a scalable route to the production of NATMs via high-speed, continuous synthesis of large-area graphene by roll-to-roll CVD, combined with casting of a hierarchically porous polymer support. To begin, we designed and built a two zone roll-to-roll graphene CVD reactor, which sequentially exposes the moving foil substrate to annealing and growth atmospheres, with a sharp, isothermal transition between the zones. The configurational flexibility of the reactor design allows for a detailed evaluation of key parameters affecting graphene quality and trade-offs to be considered for high-rate roll-to-roll graphene manufacturing. With this system, we achieve synthesis of uniform high-quality monolayer graphene (ID/IG < 0.065) at speeds ≥5 cm/min. NATMs fabricated from the optimized graphene, via polymer casting and postprocessing, show size-selective molecular transport with performance comparable to that of membranes made from conventionally synthesized graphene. Therefore, this work establishes the feasibility of a scalable manufacturing process of NATMs, for applications including protein desalting and small-molecule separations.