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Science

Graphene Spun Into Meter-Long Fibers 159

Posted by Soulskill from the incremental-progress dept.
ananyo writes "Nano-sized flakes of graphene oxide can be spun into graphene fibers several meters long, researchers in China have shown. The strong, flexible fibers, which can be tied in knots or woven into conductive mats, could be the key to deploying graphene in real-world devices such as flexible batteries."
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Graphene Spun Into Meter-Long Fibers More

Graphene Spun Into Meter-Long Fibers

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  • Are still high.... Give it a few years and it may be cheaper.

  • This has been a sticking point for a lot of uses.

    • Re: (Score:2)

      by tsa ( 15680 )

      Yeah, like the space elevator! I'd love to see one of those be built, but that will probably only happen in my dreams in my life.

      • Re: (Score:2)

        by geekoid ( 135745 )

        The Space elevator will never happen.
        Never Happen.

        Many, many technical issues aside, the risk is too damn high.

        • Why need it be risky? As with all other things, use redundancy. Redundant cables mean no single failure will drop the elevator car. Multiple parallel cars mean loss of an entire strand won't trash the whole system, and new spools can be carried up to drop another elevator. You wouldn't be traveling at orbital velocity, so re-entry wouldn't need much in the way of shielding. One rocket burst to kick the elevator clear of the falling cable, followed by parachutes, and retro-rockets for final landing woul

        • Re: (Score:2)

          by Jeremi ( 14640 )

          Many, many technical issues aside, the risk is too damn high.

          The risk of what, exactly?

          If you mean the risk of such a structure being impossible to ever build in real life, then I agree. But still we can dream... :)

          If you mean the risk of the cable breaking, sure that's a risk, and a break would probably cost you your expensive space elevator... but that's hardly different from current technology, where a malfunction will cost you your expensive rocket.

          Or if you mean the risk of the cable breaking and causing mass destruction on the ground... then you are wrong. A

          • The numbers I've seen are not exactly low mass. The geosync point of the cable is tens to hundreds of meters in diameter. It's moving at roughly 2000 mph relative to the surface point below it.

            Severing the elevator at that point would be very bad.

            To prevent this from being a 'lash of fire' along the equator, you would have to break it up into chunks small enough to burn up in the atmosphere. This would require, what, football sized chunks? Unlike a space craft the chunks are very strong, so they are un

  • Is the magic missing technology required to construct a functional space elevator?
    • The only magic missing from that project is money.

      • Re: (Score:3, Interesting)

        by Doubting Thomas ( 72381 )

        ... and a material of the necessary tensile strength. If we had that, then the money probably wouldn't be that hard to get.

        But as someone else replied, apparently this ain't it. Or at least, not yet. A pity, really. I was hoping the same thing.

      • Re: (Score:2)

        by geekoid ( 135745 )

        Yes, lets but a super strong cable that can go around the globe 3 times and use it to tie a rock to the planet. What could [possible go wrong?

        I prefer not to have thing that can annihilate civilization as we know it just hanging around.

        • Re:Space elevator coming next? (Score:5, Interesting)

          by wagnerrp ( 1305589 ) on Tuesday December 06, 2011 @09:29PM (#38287392)
          Three times? No. By pure coincidence, geostationary orbit is just under one circumference, 89% of one to be exact. In a worst case scenario, that 22kmi comes crashing down, and doesn't quite wrap around the world once, while the counterweight gets flung out into space. You could actually cut the cable somewhere around 15kmi, and the remainder would be going fast enough to remain in orbit. Send some robot to spool it up to reduce the navigation hazard, and then collect it later. By necessity, such a thing would be placed on the equator, so between South America (Equador, Columbia, Northern Brazil), Sub-Saharan Africa, and Indonesia, pick two out of three to hit. You could place scuttling charges on that section of cable every couple miles, such that the cable harmlessly falls down much as long party streamers. The worst damage it would cause would be shorting out any electrical lines it managed to cross.

      • Well that's okay, last I checked, China had all the money.

    • Re:Space elevator coming next? (Score:5, Informative)

      by Nadaka ( 224565 ) on Tuesday December 06, 2011 @04:58PM (#38285342)

      not yet. I RTFA.

      There are mechanical defects in the graphene strand that make it weaker than traditional carbon fiber.

      They are going to need to be able to generate nearly perfect strands before that becomes an option.

      • Couldn't a cataylst be created that would "mend" a carbon fiber?

      • Re: (Score:2)

        by rwa2 ( 4391 ) *

        Eek! And they also tied it into a square knot! Couldn't they at least have had the decency to tie it into a more secure figure-8 knot?!

        • Knot identification fail (Score:2, Informative)

          by Anonymous Coward

          That's an overhand knot, not a square knot. If you want to join two like-sized ropes use the square knot; neither the overhand nor the figure-8 can do that.

          You're right that the figure-8 is better than the overhand in most ways.

          • Re: (Score:2)

            by SgtXaos ( 157101 )

            That's an overhand knot, not a square knot. If you want to join two like-sized ropes use the square knot; neither the overhand nor the figure-8 can do that.

            You're right that the figure-8 is better than the overhand in most ways.

            A square knot is properly used only as a binding knot. It can collapse and fail when placed under strain. If you want to joint two ropes (or glorious miracle graphene cables) use one of the interlocked overhand bends, such as the Carrick bend, the Zeppelin bend, or the Ashley bend.

      • Re: (Score:2)

        by TWX ( 665546 )

        They are going to need to be able to generate nearly perfect strands before that becomes an option.

        I guess we're safe from China beating us in the Space Elevator race then... Based on my experiences with Chinese-made goods their quality control will never be up to the task.

        At least all those batteries that the e-bike people order that keep coming inadequately packaged and deformed will be able to handle if the graphene can be deformed safely... *grin*

      • Re:Space elevator coming next? (Score:5, Informative)

        by wierd_w ( 1375923 ) on Tuesday December 06, 2011 @05:15PM (#38285530)

        Whenever I see "space elevator!" Mentioned, this course of action plays out in my head:

        A space elevator/orbital tether needs to be at the rotational equator. This means central or south america, or africa. (Islands would lack the strong continental plate foundations to hold the tether to the earth.)

        The tether itself will be many kilometers long. It has to extend all the way, vertically, into low earth orbit.

        The tether, if made of a conductive material like graphene, would become super charged with high voltages just from the air currents whorling around it. (Don't believe me, run a kite on copper wire and attach a volt meter between it and the ground. Remember that the kite string is orders of magnitude shorter than an orbital tether.) In addition to this constant charging, you have the high energy disturbances of the ionosphere to deal with. I suppose this could make the tether into a fantastic dc powerplant, but it would also make putting a carriage on the tether much more difficult.

        Then you have the political problems.... look at the shit that happens with selecting where to hold the olypic games. Imagine the politics involved in breaking soil on an orbital tether.

        And then, finally, what happens if there is an accident? Many kilometers of highly energized, and kinetically taught razorwire with toughness surpassing all other construction materials whipping round the planet sounds pretty dangerous to me.

        Really, the logistics of such a project just don't make for a plausible project, barring some kind of officious one world government that doesn't brook dissent.

        • Re:Space elevator coming next? (Score:5, Informative)

          by Anonymous Coward on Tuesday December 06, 2011 @05:22PM (#38285594)

          And then, finally, what happens if there is an accident? Many kilometers of highly energized, and kinetically taught razorwire with toughness surpassing all other construction materials whipping round the planet sounds pretty dangerous to me.

          I don't have the link handy, but someone actually did the math on this. Due to the mass vs. surface area (and how much energy will be lost to air resistance), the cord will land softly along the surface of the earth from the anchor to the breakpoint. The greater danger will be had by the station at the top of the cord, but there are ways to stabilize the rotation it would suffer.

          • I wasn't referring to tether breakage.

            I was referring to what happens when something big (like an orbital cargo tug) fails to dock smoothly with the transfer station, causing the station to lose ballistic control, and get punted like a tetherball into the planet's surface.

            The cable will remain taught in this catastrophe, and won't just float down nicely.

            • Re: (Score:3, Informative)

              by tmosley ( 996283 )
              I don't think you understand the amount of force that would be required to do that. Maybe if the tether got hit by an asteroid the size of Dallas. Nevermind that in the event of such a catastrophe, they could simply cut the cable at the base, and the whole thing goes flying out into space. There would be plenty of time, as it would easily take weeks to fall.

              Also, you demonstrate your lack of understanding of the space elevator concept by claiming the fiber needs to extend to low earth orbit. It doesn

        • The potential difference between the top and bottom could potentially be used to power the elevator in the first place. It wouldn't be a problem for the carriage because of physics. You know how birds aren't electrocuted when they stand on high-voltage power lines? The carriage won't have a potential difference across it, so I don't think it will be a problem. So long as the tether has someplace to discharged continuously I don't see it being a major problem.

          Also, nothing (probably) would stop you from jus

          • Re: (Score:2)

            by tsa ( 15680 )

            If politics is an issue you can always bring peace with some bombs before you start building.

          • The charge problem is one of a saturated floating ground on the carriage's electronics, not an electrocution hazard. :)

          • Re: (Score:2)

            by ppanon ( 16583 )

            Equatorial weather above the ocean tends to get much more interesting than it does above ground, for many months of the year. The type of storm that helped set the conditions for the crash of Air France Flight 447 is pretty common. Sure the cable would be pretty resistant, but the cars are going to have a nice sail area. You also would probably prefer to use beamed power to improve the mass ratio on the cars. The latter would be harder if you've got heavy cloud cover for a good deal of the year.

            The politica

            • I wonder if any Caribbean islands would be close enough, I'm sure Trinidad or Barbados (where the experimental space launch guns were built) would be happy to accept a launch facility.

        • Re:Space elevator coming next? (Score:5, Informative)

          by kybur ( 1002682 ) on Tuesday December 06, 2011 @05:38PM (#38285758)
          A space elevator can't just go to LEO, it's got to go all the way to geosynchronous orbit (42,000 kilometers up) and then past that for a counterweight.

          If we only had to go to LEO, we'd probably have done it already.

          Also, there are a ton of satellites in LEO, and most of them are likely to hit the tether at some point. It is just a matter of time (and not as much time as you'd think -- you'd probably have a near miss every couple weeks).

          • Re: (Score:2)

            by tmosley ( 996283 )
            Something tells me that no-one is going to care about LEO once the cost to GSO is dramatically reduced by the space elevator.

            • Re: (Score:2)

              by Thing 1 ( 178996 )
              Which means building the space elevator is urgent; why put more debris in LEO than we absolutely need to?

        • Not so sure about the anchor point bit, but the rest seems true.

          One of the proposals terminates the cable at a boat. I dunno how they keep the thing from being pulled downwind (other than "because it's in the doldrums"), but the tension on the cable only needs to exceed the weight of the cars, the freight, and the safety margin. If you put too much tension on the cable, you'll snap it. If you're trying to hoist an island off its foundations, that would definitely be 'too much tension'.

          • Re: (Score:3, Insightful)

            by wierd_w ( 1375923 )

            I was thinking more like this:

            Say you send a 100 ton payload up the tether. After a certain point on the ascent, you stop trolling up the fiber, and actually have to start applying breaks on it, because the centrifugal force (please, I know the difference between it and centrepital force. The former is a pseudo force, yes, but still real.) Acting on the carriage will be correlated with the inertial mass of the carriage, the rate of rotation, and the radal distance from the center of rotation, in relation to

        • Don't try to bring sanity into this! This is Big Science. Great Science Fiction novels portray it. They can't be f-ing out of their minds apeshit berserk, surely!

          And seriously, do not try to put any actual physics or arithmetic or above all, economics into it. They'll hunt you down like a dog if you do...

          rgb (and yes, I'm an avid SF reader, from Brin to Cordwainer Smith to Niven -- but just because they write cool stories doesn't make the idea feasible or even physically correct, see e.g. Ringwor

        • ...A space elevator/orbital tether needs to be at the rotational equator.

          No, it doesn't. If not on the equator, it will simply be a bit longer, and appear to go up at an angle. This might not be a bad thing either, as it's generally easier to push things up a ramp than lift them straight up.

          The tether, if made of a conductive material like graphene, would become super charged with high voltages just from the air currents whorling around it. ...

          You say that like it's a bad thing. Golly, all of those oil-free volts going to waste. And it wouldn't be all that difficult to run the car, you just gradually raise the charge on the vehicle (and the inhabitants) to the same charge as the cable before launch. Have a look at what high-

          • Not on equator:

            If it isn't on the equator, it will have an impact on the earth's axial tilt. This is a bad thing. Look up precession to see why. A space elevator would most certainly be a long term investment, and building such an investment in such a location pretty much garantees local dependence on the investment economically, and a strong disincentive to terminate the investment when problems eventually begin to manifest. See, eg, current problems with fossil fuels.

            Charged cable == bad?

            This admittedly

            • Re: (Score:2)

              by tmosley ( 996283 )
              lol, sure, a few hundred billion tons going up a space elevator over the course of human habitation is going to have an effect on the tilt of the Earth, which weights ~6E+24 kilos.

              Christ, and ant just crawled across my foot and sent me spinning into the wall. That impact sent me flying into space!

        • Re: (Score:2)

          by JSG ( 82708 )

          Given the length of this thing and its sheer mass, I don't think that the relatively short depth of the sea is likely to make much difference.

          Granted that the water will get in the way somewhat. However the construction team that puts up (drops down?) a space elevator link are probably not going to find that a problem.

          I suggest that the whole equator is fair game.

          Cheers
          Jon

        • Re: (Score:3, Informative)

          by ceoyoyo ( 59147 )

          Your head unfortunately doesn't have a good handle on space elevators.

          A space elevator doesn't HAVE to be right at the equator, although that's the easiest way. The equator doesn't go through central America.

          Islands are perfectly fine. A space elevator doesn't pull on the ground station much. If it did, your ground station would certainly fail before "strong continental plate foundations" were an asset. Actually, an artificial, mobile sea platform may be a good idea because you can move it around to tow the

          • If the counterweight drifts or is flung into space I hope it has reentry rockets.

        • And some fuck could always bring pruning shears.

      • Carbon fiber, carbon nanotubes and graphene fiber are all different forms with different properties.

    • Re: (Score:3)

      by Raul654 ( 453029 )

      You're thinking of carbon nanotubes, not graphene. Graphene is a layer of carbon only a few atoms thick, which (like carbon nanotubes) is electrically conductive, and (unlike carbon nanotubes) is also transparent. So if they can iron out the manufacturing issues, they can create transparent panels (like glass) that are electrically conduct. This has all kinds of useful applications for display panels (transparent ipads, anyone?), windows that function as TVs, monitors, solar energy collectors, etc.

      • Carbon nanotubes are just rolled up graphene. I'm sure a single nanotube would be almost as transparent as a single layer of graphene.

    • I was thinking about how the energy of chemical rockets is just barely sufficient (given fuel mass) to make chemical rockets that can escape Earth's gravity well. I'm not sure of the exact headroom but my understanding is that it is fairly tight. From what I have read on the strength of nanotubes, they too are theoretically just strong enough to barely make a space elevator a possibility (if we could manage to weave them into a macro-fiber without significant losses.) If this turns out to be the case I wond

      • Chemical rockets efficiency is all about the nozzle and reaction mass velocity. Which are all about the materials used to make the nozzle. (Simplification of course, chamber pressure also matters.)

        There are no 'laws of physics' that prevent us from building a chemical rocket that can go single stage to orbit. Their are not materials to build the nozzle, yet.

        Finally we still don't know how to make the theoretically best fuel for rockets outside the lab (metallic/monatomic Hydrogen). Even in the lab we m

      • Interesting correlation! Maybe it also plays a role as to whether or planet is suitable for life, a lot weaker and we'd lose too much of our atmosphere to space. A lot stronger and we'd end up a gas giant. But these might be pretty broad limits.

        However, once life gets started, I'm not sure that the strength of gravity is tied closely to the development of life (life evolved into quite complex forms in the oceans). As far as INTELLIGENT life, I also am not sure if there's any correlation. Perhaps our an

  • Space elevator? (Score:4, Insightful)

    by wisebabo ( 638845 ) on Tuesday December 06, 2011 @04:54PM (#38285308) Journal

    Sorry, but that's the first thing I think of when a new super material is described.

    I can't think of any other technology that, barring a really huge breakthrough (like anti-gravity) would truly make space travel a practical reality for millions. Even Arthur C. Clarke in his "Fountains of Paradise" book alluded to this saying that the supposedly hyper-efficient rockets of the future would create so much environmental damage (pollution, sonic booms) that really heavy traffic couldn't be sustained.

    Maybe if we had cold fusion (or something like it like muon catalyzed fusion or zero-point energy) space travel on a large scale would be practical but these "breakthroughs" might be just as far (or impossibly far!) away.

    By the way, did anyone see the developments (at MIT?) where they showed a nano structured "tape" able to support the weight of a full grown man with only a few inches of surface area? And it was able to be re-used thousands of times before using its grip? Perhaps the space elevator could be made of material structured this way, I mean if that thing is ever going to be built it will essentially be a gigantic 23,000 mile long SINGLE MOLECULE anyway so nano structuring should be almost trivial!

    • Compared to airplane travel, would several hundred rocket launches a year really contribute that much more pollution?

      • Again, I'm just paraphrasing from his book (but I think I'm remembering it correctly). It was a scene where they were pitching the idea of the space elevator and talking about the fact that the (unspecified) rockets of he future would be producing unacceptable environmental damage.

        In his defense I think he was talking about "astronomical" (ha ha) levels of space traffic, something we can only hope for in our wildest dreams of a true space faring civilization with millions going to space DAILY. But who kno

      • Re: (Score:2)

        by 0123456 ( 636235 )

        Compared to airplane travel, would several hundred rocket launches a year really contribute that much more pollution?

        Gaseous-core nuclear rockets are pretty polluting. LOX/LH2 not so much.

      • Rockets are certainly much dirtier than commercial jet engines so they're not directly comparable. Every little bit helps, and a space elevator would be cheaper too, so it's a win/win.

    • Re: (Score:3)

      by F34nor ( 321515 )

      See "Space Fountain." Build-able with current technology. Basically use a particle accelerator to provide lift to the building, at the top have a turnbuckle that sends them back to the accelerator, rinse and repeat. Like trying to raise a full fire hose in the air vs. a tape measure.

      http://en.wikipedia.org/wiki/Space_fountain [wikipedia.org]

    • I agreed all the way till, "...so nano structuring should be almost trivial!"

      Ouch! But I could be wrong, could you point to us your web page of similar trivialities with nano structuring? I think that's were I have some questions.

  • the nanostructure is porous (Score:5, Interesting)

    by wierd_w ( 1375923 ) on Tuesday December 06, 2011 @04:59PM (#38285348)

    To me, this suggests a couple more interesting applications:

    Battery electrode
    Supercapacitor dielectric
    Chemical sensor
    Nanofiltration
    Lightweight structural blocks/foams (this is essentially a spun aerogel with a water solvent...)
    Carbon wire (copper is expensive)

    I am sure there are others.

    • I can attest that it's being researched for numbers 1-3. Numbers 4-5 are likely but outside my field. #6 is currently unlikely as graphene is a helluvalot more expensive than copper.
  • my first thought was how soon will graphene yarn become available?

  • "Carbon fibre is made by a high-temperature treatment. Our fibres are made just by spinning a water-based solution â" it is quite green and quite easy,"

    We should make kink-springs out of this stuff, since gene-hacked algae can be dangerous if the tanks are contaminated.

    • Re: (Score:2)

      by Jeremi ( 14640 )

      We should make kink-springs out of this stuff, since gene-hacked algae can be dangerous if the tanks are contaminated.

      IIRC the real hazard was the overworked wooly mammoths running amok and trampling people. Why nobody bothered to simply set up some solar panels instead, I'll never know.

  • I predict cancer (Score:4, Interesting)

    by OrangeTide ( 124937 ) on Tuesday December 06, 2011 @07:42PM (#38286796) Homepage Journal

    I expect the effect of graphene on the human body to be similar to asbestos. So expect increased cancer rates, Asbestosis, and other health problems from people who work with it as a raw material.

    • Re: (Score:2)

      by Twinbee ( 767046 )
      Graphite can be 'peeled' to make graphene so easily that I doubt it could be *that* bad.

    • Re: (Score:2)

      by sgt101 ( 120604 )

      Why do you expect this : have you done phage tests? Do you have information on the stability of the reduced material with respect to physical disruption?

      • This is my point exactly, the information simply does not exist, it's as if someone didn't even bother to look into the possibility. I'd rather the consequences were determined up front, instead of waiting for a few workers get injured or sick to provide evidence to support such an investigation. There is already quite a bit of question concerning the safety of Fullerenes (buckyballs, carbon nanotubes, etc). I would rather err on the side of caution, as an otherwise harmless material such as graphite, is ma

    • Aw damn I was just thinking about graphene car body panels :-(

      I wonder if a few layers of clearcoat would safely seal it in? Just hold your breath if you get in an accident :-P

  • not graphene (Score:4, Interesting)

    by Goldsmith ( 561202 ) on Tuesday December 06, 2011 @08:16PM (#38287040)

    Graphene oxide and graphene are two different materials. As different as iron and rust, particularly in electrical properties.

    This deliberate misleading of people outside the field by nanotechnology researchers is a major problem and has been for several years.

    • RTFA. Graphene oxide is an intermediate stage. From the article: " A final chemical reduction treatment turns the long strings of graphene oxide back into graphene."

      So the final product is definitely graphene.

      • Re:Definitely is graphene (Score:4, Informative)

        by Goldsmith ( 561202 ) on Wednesday December 07, 2011 @01:59AM (#38288562)

        Wait, I just told you the guys writing about graphene oxide are misleading you, and your response is that I should read their article? Think about that for a minute.

        I am a graphene researcher. I've published my own papers on these materials. I've done my own measurements. The resistance, carrier mobility, noise power and chemical reactivity of reduced graphene oxide is not the same as graphene. That's what their data says too, the press release text from Nature doesn't matter.

        • No, the one being misleading was you. You wrote: "Graphene oxide and graphene are two different materials. As different as iron and rust, particularly in electrical properties."

          The Nature news article says explicitly that the Zhen and Chao material is "conductive"; graphene oxide is an insulator. So the new material, however imperfectly reduced, is undeniably closer to graphene than to graphene oxide. It's definitely closer to iron than to rust, to use your analogy.

          Implying otherwise, as you have done tw

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