Graphene, the thinnest and strongest substance known to science, could be used to help detoxify nuclear waste thanks to the latest discovery involving the wonder material.
Experiments show that it can act as a “super sieve”, able to separate different atomic isotopes of hydrogen, and create the expensive “heavy water” needed by the nuclear industry, researchers said.
This is the first time that graphene – which consists of a crystal lattice of carbon arranged in layers just one atom thick – has been shown to act as a subatomic filter.
Ref: Sieving hydrogen isotopes through two-dimensional crystals. Science (1 January 2016) | DOI: 10.1126/science.aac9726
One-atom-thick crystals are impermeable to atoms and molecules, but hydrogen ions (thermal protons) penetrate through them. We show that monolayers of graphene and boron nitride can be used to separate hydrogen ion isotopes. Using electrical measurements and mass spectrometry, we found that deuterons permeate through these crystals much slower than protons, resulting in a separation factor of ≈10 at room temperature. The isotope effect is attributed to a difference of ≈60 milli–electron volts between zero-point energies of incident protons and deuterons, which translates into the equivalent difference in the activation barriers posed by two-dimensional crystals. In addition to providing insight into the proton transport mechanism, the demonstrated approach offers a competitive and scalable way for hydrogen isotope enrichment.