Visual abyss: How black is the world's blackest material?

The world’s darkest material may have gotten even darker, defying even spectrometers, which cannot quantify its blackness.

Surrey NanoSystems’ Vertically Aligned Nanotube Array black, or Vantablack, was developed in 2014 as the blackest known substance on Earth. Vantablack was originally created for use on satellites, but its high light absorption and ability to convert the trapped light into heat have made it a desirable product across scientific and commercial domains.

The blackness of Vantablack is so extreme that it confounds the eye. “It is so dark that the human eye cannot understand what it is seeing. Shapes and contours are lost, leaving nothing but an apparent abyss,” Ian Johnston of The Independent wrote in 2014.

Vantablack is made up of “a ‘forest’ of aligned and equally spaced, high aspect-ratio carbon nanotubes,” according to Surrey NanoSystems’ product description. Photons entering the thicket of tubing become trapped in the microscopic system and are bounced between the carbon tubing, eventually becoming heat before dissipating. The scientific development company says that the composition of the tubes means that Vantablack coating is almost entirely made up of free space, making it extremely light, flexible, and durable - although applied pressure such as touch can damage the nanostructures.

Vantablack can be utilized either through its original low-temperature chemical vapour deposition adhesion, or via the newly developed Vantablack S-VIS spray. Surrey NanoSystems originally said Vantablack could absorb 99.965 percent of visible light, although the company’s measurement systems are unable to quantify the material’s current blackness. The S-VIS spray is slightly less black than the original product, but to the naked eye the two look the same.

“The original Vantablack coating marked a major milestone, and is fundamental to many companies developing higher-performance equipment,” Surrey NanoSystems’ chief technology officer Ben Jensen said in a company release about the S-VIS product.

“We continue to develop the technology, and the new sprayable version [opens] up a whole new range of applications. Vantablack S-VIS is so effective that its performance far outstrips any other known paint or super-black coating,” he said.

Mr. Jensen added that the Vantablack fabrication’s low reflectance surpasses that of the materials currently used to manage light in the Hubble Space Telescope. In addition to satellites, Vantablack could be used in telescopes like the Hubble to further eliminate excess light and get clearer images of space. Surrey NanoSystems lists a variety of other potential applications for the ultra-black coating in fields including solar energy, luxury goods, spectrometry, sensors and calibration, and even art and architecture. In fact, artist Anish Kapoor acquired the exclusive licensing to use Vantablack in his studio’s art.

The quest for the ideal “black body” has been ongoing since the 19th century, when scientists theorized about a substance that could “completely absorb all incident rays, and neither reflect nor transmit any.” While Vantablack may not have yet reached the complete retention sought after since then, it is close enough for those interested in a non-reflective coating for their work.

The ongoing enhancement of Vantablack to its current unmeasurable blackness is good news for the industries that hope to utilize the light absorbent, and its potency is being shown off by Surrey Nanosystems even as they continue to improve it. A new video posted by the company shows just how effective the material is at reducing reflection. And The Science Museum in London will host a Vantablack exhibition through the start of June, showcasing its blackness and the illusion of shapelessness it creates when applied to objects.