Okay, so it ain’t no Egyptian cotton, but a team composed of researchers from MIT, the University of Michigan, and the Indian Institute of Technology has come up with a new way to fabricate a graphene sheet, which overcomes some of the hurdles that have been bedeviling researchers ever since the quirky material was discovered in 2004. Ironically, the new technique harkens back to those early days, when a tiny sheet of graphene was first separated from a chunk of graphite by literally peeling it off with common sticky tape.
Graphene Sheet: The Sticky Tape Solution
For those of you new to the topic, graphene is a one-atom thick sheet of carbon, which despite its nano-skinny physique possesses more superpowers than [insert favorite superhero here]. Its unique properties as a conductor make it ideal for clean tech applications including next-generation batteries and solar cells (and more solar cells).
Of course, there’s a catch. Graphene is notoriously finicky and difficult to produce at commercial scale.
Various methods have been cooked up to produce small flakes of graphene, but so far the fabrication of larger sheets has proved elusive.
The current method of choice is to grow graphene as a film on metal foil, with nickel or copper being the most common. Then the foil needs to be sloughed off somehow in order to use the graphene sheet, and that has posed difficulties of its own.
The new MIT/U-Michigan graphene research veers off in a new direction by growing graphene film directly onto a substrate that has some kind of use, so the entire film/substrate combo can be handled together.
The technique still involves a metal layer, but it is insulated on one side by a layer of glass (silicon dioxide, to be specific).
How To Make A Graphene Sheet
Here’s how it works. You make a thin layer of nickel on a sheet of glass, and then you get yourself a chemical vapor deposition setup (pretty sure they carry that at Lowe’s), and you deposit a film of graphene on the layered sheets.
That means you have a nickel layer with a graphene surface, and a glass layer with a graphene surface. Peel away the nickel/graphene layer and there you have it: a nice sheet of graphene-coated glass that can be used for any number of purposes.
As described by David Chandler of MIT:
…there’s no need for a separate process to attach the graphene to the intended substrate — whether it’s a large plate of glass for a display screen, or a thin, flexible material that could be used as the basis for a lightweight, portable solar cell, for example.
It’s not clear what you’re supposed to do with the graphene that lands on the nickel side, but maybe you can recycle that.
For that matter, the research is still in the early stages. The next steps will involve shaping up the quality of the graphene sheet into shape for commercial application.
Graphene’s Guardian Angels
While we’re hanging around the topic, let’s give a shoutout to the glass manufacturer Guardian Industries, which partnered up with the research team to produce the glass sheets at one of its massive facilities.
Also sharing the spotlight is the National Science Foundation and of course, the Air Force Office of Scientific Research, which has been plowing some mighty impressive research energy into graphene.