Transcript
With properties that promise faster computers, better sensors and much more, graphene has been dubbed the "miracle material." However, progress toward producing it on an industrial scale without compromising its properties has proved elusive.
Fortunately, University of Groningen scientists have now made a significant breakthrough, as recently reported in the journal Nano Letters.
Graphene is an extraordinary carbon molecule, just one atom thick, that looks like nanoscale chicken-wire. Electrons pass through it with hardly any resistance at all, and despite being very flexible, it is stronger than any metal.
The discoverers of graphene, Andre Geim and Konstantin Novoselov, famously made it by peeling graphite with Scotch tape until they managed to isolate a single atomic layer of graphene. That accomplishment won them the 2010 Nobel Prize in Physics.
Today, the biggest barrier to commercialization is finding a substrate that enables scalable production and preserves the properties of graphene.
A good candidate is chemical vapor deposition, in which heat is used to vaporize a carbon precursor like methane, which then reacts with a catalytically active substrate to form graphene on its surface.
A transition metal, such as copper, is normally used as the substrate that acts as a support for the newly formed graphene. However, it also tends to interact with the graphene and modify its properties.
v To restore those properties after growth on the metal, the graphene has to be transferred to a non-interacting substrate, but this transfer process is cumbersome and often introduces defects.
Nevertheless, many scientists are trying to improve graphene growth on transition metals, mostly using copper foil as the substrate. The team also reports the remarkable finding that graphene on copper oxide is decoupled from the substrate, which means that it preserves its peculiar electronic properties.
The results could be far-reaching. The best-case scenario would be that large, single-domain crystals of graphene could be grown on copper oxide. If this proves to be the case, it should then be possible to use lithographic techniques to make all sorts of electronic devices from graphene in a commercially viable manner.
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