Become a fan of Slashdot on Facebook

 



Forgot your password?
typodupeerror
×
Space Science Technology

NASA Creates Super-Black Carbon Nanotube Coating 132

An anonymous reader writes "NASA has just revealed a new, super-black material, claiming it is the most light absorbent material ever developed, and capable of absorbing 99% of ultraviolet, infrared, far-infrared, and visible light. The super-black material is about 10,000 times thinner than a human hair and created using carbon nanotubes. Those nanotubes are positioned and grown on multiple other materials including silicon, stainless steel, and titanium. The process of applying the coating requires heating the surface up to 1,382 degrees in an oven filled with a 'carbon-coating feedstock gas.' As well as being up to 100x more absorbent than anything that has come before, the coating is significantly lighter than the black paint and epoxy commonly used today to absorb light. Because the light absorption level is so high, the super-black material will also keep temperatures down for the instruments it is used on. And that very high absorption rate brings one final big advantage: it allows measurements to be taken at much greater distances in space because it removes the light emitted from around planets and stars as well as any generally high-contrast area of space."
This discussion has been archived. No new comments can be posted.

NASA Creates Super-Black Carbon Nanotube Coating

Comments Filter:
  • Black don't crack. And neither will these nanotubes.

  • Picture (Score:5, Funny)

    by leetrout ( 855221 ) on Wednesday November 09, 2011 @07:44PM (#38006550) Journal
    Here's a photo of it. In the middle, kinda hard to make out http://f.cl.ly/items/1S2W2w3X0z13450i440Z/black.jpg [f.cl.ly]
  • 1,382 degrees F (Score:2, Interesting)

    by ackthpt ( 218170 )

    Since the scale wasn't mentioned, unless you read TFA.

    Hmm. This would be awesomes for people who put solar heat collectors on their roofs in the Great White North. I wonder how soon it can be done affordably.

    Better market prospect for that than Solyndra.

    • Yeah, if this absorbs from ultraviolet to infrared that well then how much heat would it transfer? If you have an air gap of inner and outer walls in a research station in the north or south poles with this material lining the inner wall would it re-absorb much of the lost heat? Would layering this stuff between air gaps suck in more heat than you lose in temperatures that cold?

      • by ackthpt ( 218170 )

        Yeah, if this absorbs from ultraviolet to infrared that well then how much heat would it transfer? If you have an air gap of inner and outer walls in a research station in the north or south poles with this material lining the inner wall would it re-absorb much of the lost heat? Would layering this stuff between air gaps suck in more heat than you lose in temperatures that cold?

        Well, my father, a CE, had a friend who build a large collector for his roof, back in the 1970's. He collected aluminum cans, cut the tops and bottoms off, halved them and anodized the inside of the halves in some fashion. He arranged these as an air path in a frame on the roof of his house, southern exposed and used a small fan to run a current of air through it. Free heating during the day and it worked quite well for far less than running the furnace.

        Forward to today and an enterprising company could

      • Would layering this stuff between air gaps suck in more heat than you lose in temperatures that cold?

        Unfortunately not; such a hypothetical material would allow you to create a temperature difference out of nothing. The best way to limit radiative heat transfer is by having two reflective surfaces, such as aluminum foil. In addition to that, you need to prevent heat transfer due to air convection. That's why thermostat flasks are vacuum and shiny on the inside.

    • I did wonder about the exact temperature required and naturally assumed it was a carefully controlled centigrade temperature. Of course, it's just another case of mis-conversion from one unit to another. 1382 F is the exact conversion from 750 C, a value only given to 2 sf. 1400 F would be a more appropriate conversion if you have to convert it at all.
    • I wonder how soon it can be done affordably.

      Got a kiln capable of a controlled 1382 degrees (Farenheit), and a source of "carbon coating feedstock gas"? Sounds like an extremely affordable process already.

    • And 1382F implies a precision that isn't there. I highly doubt the process needs to be heated to the exact degree. This is simply a conversion from 750 degrees Celsius. Most likely 750 is rounded and would be +/-5, which is +/-41 F. If they were going to convert then 1380F would have been more informative or even 1400F.

      The act of conversion from on unit to another does not add precision.

    • Hmm. This would be awesomes for people who put solar heat collectors on their roofs in the Great White North. I wonder how soon it can be done affordably.

      There are already vacuum-evacuated solar-thermal panels for this. With such a system you can use a solar water heater in the arctic (although you might use it to heat the cold water). Of course these may help improve their efficiency.

  • One of the first uses will be the cover of the "Smell The Glove" re-issue

  • by wierd_w ( 1375923 ) on Wednesday November 09, 2011 @07:53PM (#38006642)

    Seriously, this was released to the media about 3 years or so ago, and touted as "scientists create blackest material ever".

    Here is a link to a wired magazine article from march 2009:

    http://m.wired.com/wiredscience/2009/03/ultrablack/ [wired.com]

    Must be a slow news week.

    • by Ugarte ( 42783 )

      wow you're right... someone even made my very dumb joke about 2 years or so ago

    • Just your normal slashdot news cycle. 3 years is a fairly short cycle, because of all the editorial work and verification that they do.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      seriously, try actually reading the article. It clearly states that they have improved the absorption by 10 to 100 times over previous nanotube coatings, and improved the wavelength range by 50 times.

    • It was first developed, to the best of my knowledge, jointly by researchers at RPI and Rice in Jan 2008. Here's their presentation [cormusa.org] and here's a link [rpi.edu] showing the date.

      In fact, their material is ten times darker than the one apparently developed by NASA, with a reflectivity of 0.05% compared to NASA's 0.5%.

    • I just heard a seminar from the guy who discovered nanotubes ( http://en.wikipedia.org/wiki/Sumio_Iijima [wikipedia.org] ), and it's pretty amazing with all the various properties the tubes have. He showed us some, and it was black (and he talked about this). He also mentioned that they would be the future for smartphone touch screens but that Apple was reluctant to use them in the latest iPhone.

      Now when his group or some other researchers discover a thin material black enough to block gamma wavelengths, then we'll be t
    • Still it's nice to have some proper "news for nerds" once in a while.

    • by geekoid ( 135745 )

      No it's not. This absorbs more light. read both articles. There are dupes, and there are people who think the story is a dupe because the don't understand some thing can be improved.

  • i wonder if this stuff will find applications in night-vision cloaking (far infrared), or in making more efficient solar cells by absorbing nearly all useful incident light?

    could it be used on CCD arrays to make them more light-sensitive?

    • by jamesh ( 87723 )

      i wonder if this stuff will find applications in night-vision cloaking (far infrared)

      Unless this material has some new property, wouldn't it also radiate better than any other material?

      • Unless this material has some new property, wouldn't it also radiate better than any other material?

        It probably -- but not necessarily -- has high emissivity to match its high absorbency. It almost certainly does not have low emissivity.

        Which means when used in far-infrared astronomical observations, the telescope would still have to be cooled to extremely low temperatures to minimize the emissions from the surface. It would still have the advantage of not reflecting infrared from other sources into the telescope.

        And yeah, it'd be useless for infrared cloaking, where the entire problem is emitted light

        • It probably -- but not necessarily -- has high emissivity to match its high absorbency

          * At the frequencies in question.

    • I'd like to see a spin off of it that can absorb cosmic rays easily, then we could coat our spacecrafts with it. You know -- when we have them again.... :-\

    • For an infrared cloack you need an astounishingly good insulator with some kind of venting, not a heat absorber. For a more efficient solar cell (photovoltaic cell implicit there?) you need a better solar cell, what is completely unrelated to this thing. The same applies to CCD arrays.

      Now, about some other uses. For a good insulator that things isn't usefull at all. If you put it facing an air (or vacuum) gap, you'll make it a poorer insulator, not a better one. For thermal solar electricity generation you

  • I think I've just found the material I want for the pigment of my next tattoo.
    • I think I've just found the material I want for the pigment of my next tattoo.

      1400 degrees F, man, if you thought needles were painful....

  • ...it ain't black, it's charcoal grey.
    <g>

  • by stms ( 1132653 )

    This sounds like the perfect material to cover up those pesky stars. [xkcd.com]

  • by Anonymous Coward

    1,382 degrees ? how exactly did they come up with that number? Here is Google at help:
    1,382F = 750 C

    • by qubezz ( 520511 )
      Even if they can't do significant figures, at least they told us how big they are in International Hair-Thickness Units...
  • The article states: "The blacker the material, the more heat it radiates away." I always thought that since black materials don't reflect light that they absorb heat. I have always heard that black clothes and black cars are hotter. However, I once read that the Blackbird SR-71 was painted black for the cooling effect. Could someone make sense of this for me?
    • Black is both a better radiator [wikipedia.org], and a better absorber. As for the SR-71 [wikipedia.org] "Finished aircraft were painted a dark blue, almost black to increase the emission of internal heat (fuel acted as a heat sink for avionics cooling) and to act as camouflage against the night sky." So, it was a combination of things.

      • ISTR reading about the composite skin on newer stealth aircraft; these skins are laminated carbon fibre with surface profiles similar to golf balls, designed to both absorb and scatter RADAR to give the aircraft the RADAR profile of a sparrow or similar. Think also really, really expensive fishing pole or reinforced carbon-carbon yacht hulls (which use the surface characteristics to create an air bubble across the entire surface of the hull during motion to reduce friction between it and the water).

    • The infra red space telescopes are positioned out of the sun ('behind' the earth) in order to keep cool. However, there's still the heat from the electronics, and there's no way to get rid of that apart from by radiating the heat away. Black radiates well, hence colouring it black will keep the spacecraft cool.

      In sunlight, more heat is coming in than going out, hence black cars get hot, and normal spacecraft are coloured silver (or similar) to make them highly reflective and bounce the heat off. (Even those

      • I'm guessing that the Blackbird SR-71 got so hot with the engines.

        At Mach 3+, you get significant heating from friction with the passing air (thus, ablative heat shields on re-entry capsules, shuttle insulation tiles, etc.)

        The fun part about the Blackbird was the way it leaked fuel... it's worth doing a little reading about the Blackbird, it's one of the more radical machines ever built, and far more entertaining than refined chimney soot.

  • by Anonymous Coward

    I see nanotubes and I want them painted black...

  • The Republican party is now researching ways to allow candidates to withstand temperatures of 1,382.

    (You might need to be a Daily Show viewer to understand...)

  • Being the color of Severian's cloak in Shadow of the Torturer.

  • If the nanotubes absorb light, wouldn't instruments coated with the material tend to get warmer rather than stay cooler?

    NR

  • "There is none Blacker"
  • by Hoi Polloi ( 522990 ) on Wednesday November 09, 2011 @11:05PM (#38008322) Journal

    "It's like, how much more black could it be? And the answer is none, none more black."

  • They're gonna paint the new Stealth Fighter with it. Or, they already have a 99.999% version ready to go for the B-3 Opportunity...
    • You seem to be under the impression that this material can only be used for one thing at a time.

      Thankfully, NASA doesn't have to wait until the military is finished using it.

  • I'm more interested in seeing what the material looks like at a standard scale, preferably in a well-lit room and in motion. It reminds me (as its predecessor did a few years back) of the fuligin cloaks worn by torturers in the Book of the New Sun. One property of those was that due to the high absorption of light, they looked less like a thing of substance and more like a void or a deep shadow. I can imagine that you'd lose all shape information save for the outline of the material and whatever it is co

  • Does this mean that it has a huge negative "thinness"? Sigh.
  • If the American government is not going to fund NASA (properly), can they at least put up a paypal account/donation thingy or something?

    >$US600Billion for military
    $US20Billion for NASA

    Sorry, but as a foreigner I'm happy to throw a couple of regular bucks for a good cause.

  • ... solar collectors. One could make a hell of a hot water heater from a base that absorbed 99% of the (visible part of the) spectrum. One could make a fairly impressive collector for the generation of electricity as well. Imagine a 1 km^2 south-facing hillside covered with flat black panels under a transparent insulated airtight roof, leading up to a hilltop tower filled with turbines (top of tower some km or so above the air intake at the base of the hill). 700 megawatts (or so) peak absorption, eve
    • Those greenhouse turbine thingies have been proposed since the 1970's, ultra-black wouldn't really improve them enough (compared to cheap 90% black paint) to make it worth using. Aren't they building a couple of prototypes in Australia and Spain?

      I'm sure this material will make it into projects like space telescopes, and probably the high mountain observatories too. There are just so few applications that really care about that last fraction of a percent of reflectivity.

      • Yes (to Australia and Spain -- in Spain a small prototype has already been built -- I think it is 50 kW or thereabouts -- Spain is a GW IIRC. They've been proposed for the US southwest too, but not yet successfully. Building on a hillside would halve the cost and potentially double the yield.

        As far as improving the efficiency -- 9% of 100 MW is 90 MW. 90 MW times (say) 2000 hours in a year is 180 GW-hours. A KW-hour is worth (say) a dime. Dividing by 10^4 to obtain dollars, using 99% instead of 90%
        • In my math, 9% of 100 is 9.

          • Ah, yes, well, hmmm divide all answers by ten, hmm -- look, over there! Are those ponies?

            (Ducks and runs away...)

            Although I suck at arithmetic, the point is still the same. There is a point where the marginal return of the coating makes it a break-even proposition, and it isn't so low as to be completely unreasonable at $10-20 per m^2 -- a large-scale production facility serving a world market devoted to producing rooftop solar house/water heaters/coolers (e.g. buffered by underground water-coupled
            • I'm not certain I'm correct, either. But... nifty as the greenhouse turbines are, I think non-reflectivity hits a point of diminishing returns for them, maybe at 90-95% if the cost of the paint increases by 2x, maybe somewhere else. I _almost_ put reflective paint inside my attic, but opted for the traditional additional 6" of fiberglass instead, cost about the same, and I'm pretty sure the fiberglass serves me better, inside the house at least.

              To me, the greenhouse would best be served by improved insula

              • No real arguments. The right place to resolve these questions is in mid-scale prototypes where you can measure and quantify and the cost/benefit of alternatives. I've got a really good location for one. Now if I just had a few million dollars...:-)
                • Site locations seem to be one of the major challenges for the greenhouse turbines... anywhere close enough to population, or even transmission lines, to get enough land with an ideal hill, will tend to be relatively expensive compared to being out in the middle of the desert where nobody needs the electricity. I can imagine a few places in Australia, or perhaps the American Southwest, that might be feasible.

                  • I think it is a lot easier than that to find good locations. There are mountains all up and down the Appalachians that are pretty much nothing but trees on a slope. The Rockies, the Sangre de Christos, the Sierras. Easily hundreds of thousands of square kilometers of more or less fallow, south facing slope with order of a kilometer of vertical rise. The main difficulty is just picking >>a
                    The idea is old enough (1926 according to wikipedia, although I had it independently) -- there are several p
        • by geekoid ( 135745 )

          " 9% of 100 MW is 90 MW"

          You might want to read that out loud.
          If it still seems correct, please take a math class.

  • If this works right, it might absorb radar and other emissions. If so, then this would be a good coat for military aircraft.
  • This just means that those 'black projects' the Pentagon is so fond of funding will be even blacker.

Arithmetic is being able to count up to twenty without taking off your shoes. -- Mickey Mouse

Working...