A brief word on a new supermaterial

Tom James @ 05-05-2009

graphene-transistorGraphene: a material consisting of a sheet of carbon atoms one atom thick. Graphene was first identified only a few years ago, and has since been proferred for all sorts of uses, including ultracapacitors, spintronics, and now as a light source:

Microchips is just one of the material’s potential applications. Because of its single-atom thickness, pure graphene is transparent, and can be used to make transparent electrodes for light-based applications such as light-emitting diodes (LEDs) or improved solar cells.

It is also apparently very strong:

The mobility of electrons in graphene — a measure of how easily electrons can flow within it — is by far the highest of any known material. So is its strength, which is, pound for pound, 200 times that of steel.

The problem is to find a way to mass-manufacture it:

The trick that enabled the first demonstrations of the existence of graphene as a real separate material came when researchers at the University of Manchester applied sticky tape to a block of graphite and then carefully peeled off tiny fragments of graphene and placed them on the smooth surface of another material.

“They don’t care if they go to a lot of effort to make five tiny pieces, they can study those for years.” But when it comes to possible commercial applications, it’s essential to find ways of producing the material in greater quantities.

[from Physorg][image from Physorg]


Smokin’ up the elevator

Tom James @ 23-01-2009

smoke_artSpace elevator prospects have improved with the development by Cambridge scientists of a method for creating longer, less brittle carbon nanotubes by combining multiple nanotube strands:

Currently, the Cambridge team can make about 1 gram of the new carbon material per day, which can stretch to 18 miles in length. Alan Windle, professor of materials science at Cambridge, says that industrial-level production would be required to manufacture NASA’s request for 144,000 miles of nanotube. Nevertheless, the web-like nanotube material is promising.

“The key thing is that the process essentially makes carbon into smoke, but because the smoke particles are long thin nanotubes, they entangle and hold hands,” Windle said. “We are actually making elastic smoke, which we can then wind up into a fiber.”

Also worth checking out some of the alternatives to traditional space elevators that aren’t so demanding of tensile strength, like Keith Lofstrom’s launch loop, an electromagnetically “inflated” orbital launch system. [thanks to Bruce Cohen (SpeakerToManagers)]

It’ll be fun to see which of these designs actually gets off the ground: just as long as they don’t get off the ground then return unexpectedly.

[from Physorg][image from neilbetter on flickr]


Graphene ultracapacitors

Tom James @ 16-09-2008

hexagonsMore developments in the field of ultracapacitors, this time using graphene (like a single layer of the graphite molecule, apparently), from researchers at the University of Texas:

“Through such a device, electrical charge can be rapidly stored on the graphene sheets, and released from them as well for the delivery of electrical current and, thus, electrical power,” says Rod Ruoff, a mechanical engineering professor and a physical chemist. “There are reasons to think that the ability to store electrical charge can be about double that of current commercially used materials. We are working to see if that prediction will be borne out in the laboratory.”

My understanding is that a key part of solving the two problems of anthropogenic climate change and the depletion of primary energy resources involves finding new and more efficient ways of storing energy.

Ultracapacitors are on option, synthetic petrol is another, or hydrogen fuel cells.

It will be interesting to see which technology (if any of these) becomes dominant as a means of storing energy.

[story from Physorg][image by procsilas on flickr]