"Scientists have fashioned what may be the blackest material in the universe: a sheet of carbon nanotubes that captures nearly every last photon of every wavelength of light.
The substance absorbs between 97 percent and 99 percent of wavelengths that can be directly measured or extrapolated. It's the closest that scientists have yet come to a black body, a theorized state of perfect absorption whose closest analogue is believed to be the opening of a deep hole.
The material, described Monday by Japanese nanotechnologists in the Proceedings of the National Academy of Sciences, is made from a flat array of vertically-aligned, single-walled carbon nanotubes. Photons that aren't immediately absorbed by a single nanotube deflect off and are absorbed by its neighbors..."