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Nanotubes Form The Darkest Material Yet Created

toxcspdrmn writes "Bad news for Spinal Tap fans. The BBC reports that researchers at Rensselaer Polytechnic Institute in Troy, New York, have produced the darkest known material by manufacturing "forests" of carbon nanotubes. This forms a surface that absorbs or scatters 99.9% of all incidental light."

23 of 324 comments (clear)

  1. Where's my fuligin? by category_five · · Score: 2, Interesting

    I can't wait to get my fuligin cloak!
    http://en.wikipedia.org/wiki/The_Book_of_the_New_Sun/

  2. Absorbtion by Psychotria · · Score: 5, Interesting

    If the light is absorbed 99.9%, where does the energy go? Heat? If so, could this lead down the road to new power sources? Super-black nanotube network produces heat to produce steam to turn turbines... (??)

    1. Re:Absorbtion by blackest_k · · Score: 3, Interesting

      From the BBC article
      "The application will be to things like more efficient solar cells, more efficient solar panels and any application where you need to harvest light," he added.

      There was an earlier article on /. with a related technology essentially printing small antennas on a plastic film which essentially create a high frequency ac voltage from heat and light energy , if the nanotubes are conductive perhaps the two technologies be combined to make some extremely efficient solar panels.

    2. Re:Absorbtion by Anonymous Coward · · Score: 1, Interesting

      Nanotubes are made from single-atom thick sheets of carbon that are rolled up into a tube. Depending on how you roll them up (along the x-axis, y-axis or diagonally) they will be conductive, semiconductive or non-conductive. I don't remember which shape causes which conductivity. However, it's tought to deterministically force a whole batch to roll up one way (one of the problems of using them for logic on computer chips). Plus they have a very high contact resistance.

      In either case, the article seems to think this might be able to be used for solar panels, so probably it will work for that.

  3. Re:I was going to ask... by bar-agent · · Score: 2, Interesting

    I'd like to see a video. All the time, I read fictional accounts of materials that "glow" black, or look so black they're unreal, like a hole in space. I'm thinking this material might look pretty much like that. So, I want to see how it responds to ambient light as it's tilted around, and what happens when you shine a flashlight on it.

    Still, if even one photon in a hundred escapes, it can't be too black, now can it?

    --
    i'd hit it so hard, if you pulled me out you'd be the king of britain [bash.org]
  4. Black body radiation by arrrrg · · Score: 4, Interesting

    IANAP but I think by being a great absorber, it becomes a great emitter too: Black body. So it may not actually get much hotter than something less black. I guess it depends on where the equilibrium point is, and I don't have any intuition about that.

  5. Re:wouldn't scattered light still be light? by protobion · · Score: 3, Interesting

    Yes but the point is , we wont let the material burn itself and everything around it. The material would start to get hot, but we will couple it to a thermoelectric/sterling etc. engine to generate power from the absorbed energy. The tubes should reach some steady state temperature and we have theoretically much more efficient light-based power source.

    --
    Essentia non sunt multiplicanda praeter necessitatem.
  6. Where to put it by xZoomerZx · · Score: 5, Interesting
    Im wondering at the practical applications of this and how much it will have to be hidden or at least above the human zone (from the floor to about 7') I imagine extreme blackness would cause an effect similar to "The Blindspot" of sic-fi space travel. In effect the eye/brain would not 'see' the blackness and pull the visible edges together in an optical illusion.

    Case in point - I was once in a room that had contained a fire. The walls, floor, ceiling, and windows were all coated in a soft black soot that was perfectly uniform and ate all the light. The effect was very disconcerting and disorienting. None of the normal visual cues of highlights, textures, or reflections existed. Only the open door gave a reference point so that you didn't feel like you were floating in a void.

    The article posits several uses, but can you imagine a person clothed in this black in full sunlight? Could we even see them? or a building covered in it? or a car? Sight requires a least some photons to hit the retina. Anyone? I know I sound repetitive, its 0430 and didn't want to lose the train of thought to sleep.

    --
    Power tends to corrupt, and absolute power corrupts absolutely.
    1. Re:Where to put it by OldSoldier · · Score: 2, Interesting

      Black like this probably has a few oddities that make it hard for us to process visually, but invisible? No.

      First, this thing's shadow is probably lighter than the thing itself!

      Somewhat related, any shadows cast on this stuff would indeed be invisible. Direct light cast on this is probably no lighter than ambient light cast on it. So... if you imagine a brick building coated in this stuff you would not be able to see the indentations of the masonry because the shadows the outward bricks would cast on the mortar joints would not be significantly darker than the color of the bricks. The upshot is that we wouldn't be able to see surface detail and that visual cue would be missing for us.

      But beyond an inability to see surface detail, we may not be able to see even the corners on a building painted with this stuff. The part of the building that's in direct sunlight would not be any brighter than the part that's not. We'd probably think it's a cylinder even if it's a square or rectangle.

  7. Stack of razorblades by Wilson_6500 · · Score: 3, Interesting

    I always thought it was kinda interesting that a stack of razorblades makes a fair approximation of a blackbody. You can't grow stacks of razorblades on surfaces, natch, but for some applications I imagine you just need a small optical sink and don't want to spend a lot of money. Then again, this could be just trivia more than something that's useful to know.

    (Because of the potential for dangerous reflections, please don't shine lasers into a stack of razors trying to test their reflectivity--unless you know what you're doing and, hopefully, have an appropriate pair of laser goggles.)

  8. The new macbook is all about being seen.... by Joce640k · · Score: 2, Interesting

    Why would you want to hide your new Macbook away?

    A great use for this would be the border area around my home cinema screen. The projector leaks a bit of light there...

    --
    No sig today...
  9. Re:Why wont this change the world? by famebait · · Score: 3, Interesting

    I was thinking along the same lines.

    But while his material would undoubtedly be very efficient for absorbing heat, it does not represent any revolution in that area: we can already absorb sunlight for heat with reasonably high efficiency with just basically black paint. This invention is better, by many percentage points, but it is still only an incremental step up from what we can already easily get per square meter.

    Also, as always, the economics come into play: it will often be a lot more attractive to use a cheaper and much simpler solution, and spend slightly more surface area to compensate for the lower efficiency.
    Extruded black plastic will probably still be hard to beat in the real world for a while.

    I think it will be much more useful in light sensitive applications.

    --
    sudo ergo sum
  10. What happens with the absorbed photons? by master_p · · Score: 2, Interesting

    Where does the energy go?

  11. Re:I was going to ask... by spydink · · Score: 2, Interesting

    what happens when you shine a flashlight on it. Or a laser...

    For example a laser used for marking targets.

    Laser applications
    --
    Always be sincere, whether you mean it or not.
  12. Re:I was going to ask... by localman · · Score: 2, Interesting

    Actually, here's a good photo of it, comparing it to the previously most black substance. It's neat: I can already imagine them using this someday in camera optics and such.

    Cheers.

  13. A Room Without A view... by flajann · · Score: 5, Interesting
    Imagine being in a room completely covered with these carbon nanotubes. Even with a bright lamp with you, you'd feel as though you're sitting in outer space. Worse even, since you'd see no stars. It would be quite stunning, and could make a cool exhibit at some science museum.

    I wonder what it would cost to do? It would be wicked cool to do this to a bedroom!!!!

    1. Re:A Room Without A view... by Doctor+Faustus · · Score: 3, Interesting

      Imagine being in a room completely covered with these carbon nanotubes. Even with a bright lamp with you, you'd feel as though you're sitting in outer space.
      It would be great for photography. You can take pictures with no background, at all.

  14. Stygium by domatic · · Score: 2, Interesting

    One of Pratchett's books talked about "stygium". It was a metal blacker than anything else in the Discworld and would incandescence and melt seconds after exposure to direct sunlight. I don't think this stuff would do that but if the spectrum is wide on this stuff, you could make some nice solar water heaters out of it.

  15. Superblack? Hardly. by Nerdposeur · · Score: 2, Interesting

    I color sampled the image of this stuff, and its RGB value is #071108. I can make a blacker square in Paint.net and print it out.

    Call me back when you reach less than #000000 and I'll be impressed.

    1. Re:Superblack? Hardly. by Nerdposeur · · Score: 3, Interesting

      Are you being funny, or are you really that ignorant?

      Well, I thought I was being funny...

  16. Re:Don't tell John Carmack! by Jellybob · · Score: 2, Interesting

    You lose the thread I'm afraid.

    #0000000 is an invalid hex code for a color to start with. I think what you were aiming for was #00000000 (that's eight zeroes for those who are counting), which is black, with a 0 alpha component (fully transparent). Which means that it absorbs no light at all, and is therefore equally dark as #ffffff00, which also absorbs no light.

  17. Re:wouldn't scattered light still be light? by jc42 · · Score: 2, Interesting

    What I'm wondering is how much hotter than a "regularly black" panel one of these would become.

    The wikipedia article others have linked to is a good intro. The brief summary: "Not much." This material would radiate the heat as a "black body". At ambient temperatures (275-300 K), this is in the far infrared, so you can't see it. You might be able to feel it, but the heat would be comparable to what you feel if you hold your hand in sunlight.

    There is real potential for applications in light-gathering gadgets, such as solar-power equipment. We'll probably start hearing about them in a few years.

    --
    Those who do study history are doomed to stand helplessly by while everyone else repeats it.
  18. Re:Don't tell John Carmack! by Solra+Bizna · · Score: 2, Interesting

    #0000000 is an invalid hex code for a color to start with.

    What if he's a heptachromat? (that would mean we get to interpret his color specification with 4 bits per color component, making 28 bits per pixel)

    -:sigma.SB

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