Graphene super membrane
Graphene, current supermaterial of choice for any number of industries, may get more popular still. A new membrane has been produced that is waterproof, breathable and incredibly light. It’s also just two atoms thick.
Scientists at the ETH Zurich worked with a team at LG Electronics to develop the material. It consists of two layers of graphene, a hexagonal lattice of carbon atoms. Using a focused ion beam (FIB) milling machine (a kind of very accurate laser cutter), the researchers drilled water molecule-sized holes in the membrane.
The two layers of carbon are necessary two prevent minor imperfections in one layer from disturbing the permeation of the whole membrane.
Its waterproof qualities mean it could be used for next-generation clothing. More importantly, however, is its potential in filtration systems. The team imagines using graphene membranes in water filters to ensure clean drinking water.
At two atoms thick, it would take 100,000 layers of the super material to produce the thickness of a human hair. At this very thin scale, the material also performs in other areas: it is over 1000 times as breathable as currently known waterproof fabrics.
Using FIB milling allows for further possibilities, as the pores that are etched into the material can be made any size. The size of these holes determines which molecules can pass through the graphene. This means it becomes possible to produce a membrane that will, for example, let through carbon dioxide rather than water.
Graphene has seen huge increase in interest in recent years. This is partly to do with the material’s simplicity. Once scientists worked out how to make super-thin layers of carbon, the research sped up. With its spectacular properties, graphene has already earned its place in science. This new development can really open the carbon material up to the whole world.
More information is available here. Images via creative commons licence.