This is quite fortuitous - i'm just now finishing a module on nanotechnology in my OU course (open university - a UK higher level distance learning university). Graphene is actually the material that carbon nanotubes are made out of. A single walled carbon nanotube is a sheet of graphene twisted into a tube with a hemispheric cap, like half a buckyball, at either end. I haven't studied what the nobel prize was for, but graphene has been around for a while. At the moment the nanotubes are mostly made by zapping an arc across graphite electrodes and condensing the vaporate out. You can also make them through a polumer and electrolysys system as well. G.

Depends. Their properties depend on a couple of things, their diameter and the "twist", or chirality, of the lattice. Depending on these depends on if they are confucters or semiconducters. What's interesting is that thwe twisting of the lattice alters the way that electrons can flow through the graphene, restricting the flow to one direction - along the axis of the fold. The tighter the fold, the less available atoms there are and the less available energy levels there are for electrons to hop about into. The configuration also determins how many "paths" there are along the axis of the fold and thus the combination of the two determins the properties. They also have an unusual Youngs modulus that allows them to be totally distorted, yet they spring back into shape. It seems to be the highest Youngs modulus of any material (or lowest, I forget which way round Youngs modulus works). It's estimated that adding 30% by volume of carbon nanotubes to a concrete mix would increase it's strength six times. G.

Rhyx wrote:

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What's interesting is that the twisting of the lattice alters the way that electrons can flow through the graphene, restricting the flow to one direction - along the axis of the fold. The tighter the fold, the less available atoms there are and the less available energy levels there are for electrons to hop about into. The configuration also determines how many "paths" there are along the axis of the fold and thus the combination of the two determines the properties.

So in short if you could find a way to "twist" and "de-twist" a length of graphene you could end up with a variable strength transistor that could alter it's properties in real time? That could save a tremendous amount of space in a microprocessor no (having one graphene transistor doing the work of a bunch by altering it's properties)? So this thing is a herald to wearable computers and further shrinking down of electronics? Seems like this material is the gateway to a space elevator and a wearable ecto all in one!

You could, I guess, but it's probably easier just to create a bunch that can work in paralel. The difficulty is altering the graphene on such a small scale to be useful on the fly - you need to do it using some kind of field like an electron tunneler, which requires a bunch of supporting aparatus, chemical (doping parts of the sheet with hydrophillic or phobic molecules to alter the configuration)or dielectrical manipulation, which is not really feasable except during manufacture. The one thing this course has shown me is how unlikely we are to ever get nanobots anything like those envisaged in EP, and how useless they would be compared to a macroscale manufaturing plant using nanoscale parts. The analogy is that nanobots would be trying to stack sugar cubes with giant, sticky fingers moved like a puppet. G.

It has been hard to manufacture uniform chirality nanotubes, but there has been some interesting work done in Germany with polymer doping and dielectric sorting that allows creation of up to 90% homogenity nanotube clusters. They can be created, sorted and arranged using a combination of the methods I mentioned above to provide arrays of nanotubes with the same properties all aligned the same way. Which is nice. G.