The name Vantablack stands for Vertically Aligned Nanotube Array black.Vantablack is a free-space coating consisting of a ‘forest’ of aligned and equally spaced, high aspect-ratio carbon nanotubes (CNTs).
The CNT array is patterned and spaced to allow photons to enter. Most of the light, or radiation arriving at the surface enters the space between the CNTs, and is repeatedly reflected between tubes until it is absorbed and converted to heat.
This heat (largely undetectable in most applications) is conducted to the substrate and dissipated. The Vantablack array is very largly free-space; the volume of CNTs only makes up about 0.05% of the coating.
Consequently, only a miniscule proportion of the incident radiation is able to hit the tip of a CNT, explaining why such a small amount is reflected back to the observer.
In 2014, British researchers invented Vantablack, which has since been declared the world’s darkest material. In fact, it’s so dark that it astoundingly has the ability to absorb 99.96% of infrared, ultraviolet, and visible light that it encounters, which is remarkable.
Surprisingly, Vantablack isn’t a pigment, fabric, or paint. It’s actually made up of millions of carbon nanotubes. These nanotubes are more than 3,500 times smaller than a human hair and work together to absorb and trap all of the light that enters.