One-atom-thick graphene works in wet and dry environments, according to research.
Graphene's atomic structure Image: Commons |
Scientists at the U.S. Department of Energy's Argonne National Laboratory have discovered that a single layer of graphene between a steel ball and a steel disk can last for more than 6,500 "wear cycles," a dramatic improvement over conventional lubricants. Traditionally, graphite only works effectively in humid environments, while molybdenum disulfide has the reverse problem.
Graphene has a two-dimensional structure which, according to the research, bonded "directly to the surface of the stainless steel ball, making it so perfectly even that even hydrogen atoms [are] not able to penetrate it."
Researchers had previously worked with a few layers of graphene. Now they have shown that, in an environment containing molecules of pure hydrogen, when the graphene monolayer eventually starts to wear away, hydrogen atoms leap in to repair the lattice, like stitching a quilt back together, when an opening appears.