Conductive graphene yarn is lighter and stretchier than copper wire
The super-stretchy graphene yarn
Copper electrical wiring may soon be facing some stiff competition – or actually, some very stretchy competition. Scientists at Pennsylvania State University and Japan's Shinshu University recently created a "super-stretchable" conductive yarn made from graphene.
The researchers started by chemically exfoliating flakes of graphene from a block of graphite. Those flakes were then mixed with water, and that mixture was concentrated into a slurry using a centrifuge. That slurry was then spread across a plate and allowed to dry, forming into a thin transparent film of graphene oxide.
The film was subsequently peeled off the plate and cut into narrow strips, those strips in turn getting wound together using an automatic fiber scroller.
The resulting yarn can be knotted and stretched without fracturing, and is said to be much stronger than other types of carbon fibers – this quality could be due to the presence of tiny air pockets within it.
Removing oxygen from the material boosts its electrical conductivity, and adding silver nanorods to it in the film-fabricating stage could reportedly boost that conductivity further, to the point of matching that of copper. Its stretchability and lighter weight, however, could make it a better alternative in many applications.
A paper on the research was recently published in the journal ACS Nano.
Source: Penn State
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An experienced freelance writer, videographer and television producer, Ben's interest in all forms of innovation is particularly fanatical when it comes to human-powered transportation, film-making gear, environmentally-friendly technologies and anything that's designed to go underwater. He lives in Edmonton, Alberta, where he spends a lot of time going over the handlebars of his mountain bike, hanging out in off-leash parks, and wishing the Pacific Ocean wasn't so far away.
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Confusing term: graphene oxide. Since graphene is merely a hexagonal array of carbon, oxidizing THAT will just yield CO2, which is useless. A web search does reveal some use of the term; it seems to mean a flake of graphene with oxidation around the edges. I guess you have to do something with the edges.
Also, you need to improve the conductivity by adding silver. Really!? Yes, silver is a great conductor. It's also very expensive. So just saying "add silver" it pretty dumb. How much silver? What does that do to the cost of the product? Now that I think of it, there's no mention of cost here at all. I have no doubt that we can make great conductors, if cost is no object. In practice, you have to compare with the cost of aluminum. If you can beat the cost of aluminum, then you have a product; if not, you just have a curiosity.
It might be possible to make it as conductive as copper, but not as cheap, surely? Mind you with copper ore enrichment now down to 0.2% and falling, how long that state of affairs will last is anyone's guess.
PiperT & Mel both have valid points. I suggest that this woven graphene is not individually good for much except as a labtoy. I do think it is one piece of some other puzzle that no may yet have thought of. This stuff is an interesting building block for something to come.
There are many misconceptions of what graphene actually is. In this case, it is a borderline definition. Graphene, a semi-metal, is a one-atom-thick, crystal-like structure; in essence, an actual two-dimensional material. In that pristine state (not particularly easy to get to, and not reachable by using the above method), anything over five layers substantially reduces it's inherent properties. Some of which are: near-transparence, extremely high heat and electrical conductivity (not needing silver or any other conductive material to help), massively strong (more than 100-times stronger than steel), bendable, inert.
The theoretical existence of graphene goes back to the late 1800s, and a scientific awareness dates back to the late 40s, but its commercial promise is only just starting to be understood, let alone realized.
This thread is not a true graphene product, but in the same family. Stuff like this shows the promise, but won't be viable for many years to come. It's a bit of a wild material with a mind of its own. It has great promise in coatings and polymers, among other applications.
Good to see the incremental progress, though. Once it can be controlled in the manufacturing process, and its properties when integrated with other materials become better known, it will be revolutionary.
You ridiculously silly goats. Silver is expensive?!!? Gold is 20 times the price and used in commonly used products as contact surfaces in your computer tower. You can buy peripheral boards with their gold contacts for $20.
Noel K Frothingham
Did no one else notice that the amount of silver used IS NOT SPECIFIED?
Noel K Frothingham
"There are many misconceptions of what graphene actually is. In this case, it is a borderline definition. Graphene, a semi-metal, is a one-atom-thick, crystal-like structure; in essence, an actual two-dimensional material."
Lucky2BHere, please explain how a crystalline structure one atom thick
makes it a "two dimensional material".. If it has a crystalline structure, that would mean that its other remaining dimensions of width and length are defined.
Noel K Frothingham
Theoretically graphene is a super conductor at ambient temperature. Copper can only conduct as well when dropped to 250 degrees below zero. Graphene oxide is an incomplete state of graphene when a chemical exfoliation method is used but is not yet not thermally annealed To burn off the oxygen atoms (considered to be an insulator) and does not exhibit conductivity at all.
Adding silver particulates to what potentially should not need any help is a ridiculous notion. Graphene oxide is not co2 as suggested here (Pipertom) co2 is a gas one carbon two oxygen (individual molecules) graphene oxide is typically hundreds of carbon atoms linked to each other in one atom layer hexagonal arrangement with oxygen atoms only connected to the edges of each flake once the oxygen is removed the graphene becomes a superconductor. When layering graphene it has been noted that over five layers begins to enact a three demensional relationship and reduces the matter back to a form of graphite and while conductive not anywhere close to pure graphene. Keeping graphene in seperation is achieved through sandwiching certain elements such as silicon or any of the halogens. Particularily usefull is iodine isotopes this has been shown to work in fuel cells as a catalist for oxygen reduction. And exhibits higher efficiencies then platinum without co2 poisoning of the conductive plates.
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