Sieving hydrogen isotopes through two-dimensional crystals
Publication Date: 01 January, 2016
Graphene – The Finest Filter
Graphene and other one-atom-thick crystals are the first ever reported sub-atomic selective membranes. A group of scientists from The University of Manchester, led by Sir Andre Geim, showed that these atomically thin membranes block all gases and liquids but selectively allow protons and deuterons (nuclei of hydrogen and deuterium – hydrogen’s heavier isotope) through. To the surprise of the researchers, deuterons permeated 10 times slower than protons.
These membranes, then, effectively sieve protons from deuterons at room temperature. The high sub-atomic selectivity of these membranes could help cleaning nuclear waste in disasters like Fukushima since tritons (nuclei of the heaviest isotope of hydrogen) are expected to permeate even slower than deuterons through graphene. The findings also open a new area of research. The ability to separate subatomic particles at room temperature allows for the exploration of a whole new and rich vein of phenomena, from biology, where the interaction of DNA with graphene is currently intensely researched, to chemical engineering, where the isotopic separation could be exploited in new chemical processes.