Vantablack

Vantablack-coated aluminium foil

Vantablack is a substance made of carbon nanotubes[1] and is the blackest substance known, absorbing a maximum of 99.965% of radiation in the visible spectrum.[2] It comprises a forest of vertical tubes which are "grown". When light strikes vantablack, instead of bouncing off, it becomes trapped and is continually deflected between the tubes before eventually becoming heat.

Etymology

Its name comes from the term Vertically Aligned NanoTube Arrays.[3]

Development

Early development was carried out at the National Physical Laboratory (UK),[4] although the term VANTA wasn't coined until sometime later.[5] The substance is now being developed by Surrey NanoSystems.[6]

Applications

This substance has many potential applications, including preventing stray light from entering telescopes, and improving the performance of infrared cameras both on Earth and in space.[6]

Ben Jensen, Chief Technology Officer, Surrey NanoSystems, explained:[6]

For example, it reduces stray-light, improving the ability of sensitive telescopes to see the faintest stars... Its ultra-low reflectance improves the sensitivity of terrestrial, space and air-borne instrumentation.

Vantablack may also increase the absorption of heat in materials used in concentrated solar power technology, as well as military applications such as thermal camouflage. The emissivity of Vantablack and scalability support a wide range of applications.

The material is being used creatively by artist Sir Anish Kapoor who said, "It's effectively like a paint... Imagine a space that’s so dark that as you walk in you lose all sense of where you are, what you are, and especially all sense of time."[7]

Improvements over previous substances

Vantablack is an improvement over previous substances developed. Charcoal reflects 4% of the incident light. The second most radiation-absorbent substance is capable of absorbing all but 0.04%. Vantablack absorbs all but 0.035%. Also, this new substance can be created at 400 °C (752 °F). NASA developed a similar substance that could be grown at 750 °C (1,380 °F). Vantablack, therefore, can be grown on materials that cannot withstand higher temperatures.[1]

The outgassing and particle fallout levels of Vantablack are low. The high levels in similar substances in the past have prevented their commercial usefulness. Vantablack also has greater resistance to vibrations and has greater thermal stability.[3]

Commercial production

As of 2014 production is being scaled up to satisfy the needs of buyers in the aerospace and defense sectors. The first orders have already been delivered.[6]

References

  1. ↑ 1.0 1.1 "Vantablack, the world’s darkest material, is unveiled by UK firm". South China Morning Post - World. 15 July 2014. Retrieved 19 July 2014.
  2. ↑ "Vantablack: U.K. Firm Shows Off 'World's Darkest Material'". NBCNews.com. 15 July 2014. Retrieved 19 July 2014.
  3. ↑ 3.0 3.1 Kuittinen, Tero (14 July 2014). "Scientists have developed a black so deep it makes 3D objects look flat". Yahoo! News Canada. Retrieved 19 July 2014.
  4. ↑ Theocharous, E.; Deshpande, R.; Dillon, A. C.; Lehman, J. "Evaluation of a pyroelectric detector with a carbon multiwalled nanotube black coating in the infrared". Applied Optics 45 (6): 1093. doi:10.1364/AO.45.001093.
  5. ↑ Theocharous, S.P.; Theocharous, E.; Lehman, J.H. "The evaluation of the performance of two pyroelectric detectors with vertically aligned multi-walled carbon nanotube coatings". Infrared Physics & Technology 55 (4): 299–305. doi:10.1016/j.infrared.2012.03.006.
  6. ↑ 6.0 6.1 6.2 6.3 Howard, Jacqueline (14 July 2014). "This May Be The World's Darkest Material Yet". Huffington Post. Retrieved 19 July 2014.
  7. ↑ "How black can black be?". BBC.col.uk. BBC News. 23 September 2014. Retrieved 7 December 2014.

External links