Scientists Invent Blackest Black
Posted on January 30, 2008
Researchers have made a substance that is so dark it absorbs more than 99.9 percent of light. It is being called the blackest black. The photo shows a National Institute of Standards and Technology reflectance standard (top), a sample of the new darkest material (center) and a piece of glassy carbon (bottom).
Shawn-Yu Lin, professor of physics at Rensselaer and a member of the university's Future Chips Constellation, who led the research project, says in a statement, "It is a fascinating technology, and this discovery will allow us to increase the absorption efficiency of light as well as the overall radiation-to-electricity efficiency of solar energy conservation. The key to this discovery was finding how to create a long, extremely porous vertically-aligned carbon nanotube array with certain surface randomness, therefore minimizing reflection and maximizing absorption simultaneously."
Pulickel Ajayan, who led the research team at Rice University in Houston, provided Reuters with these facts about the new material.
- It is composed of carbon nanotubes, tiny tubes of tightly rolled carbon that are 400 times smaller than the diameter of a strand of hair. The carbon helps absorb some of the light.
- These tubes are standing on end, much like a patch of grass. This arrangement traps light in the tiny gaps between the "blades."
- The researchers have also made the surface of this carbon nanotube carpet irregular and rough to cut down on reflectivity.
Frederik de Wilde discussed the blackest black in this Ted Talk.
Image: Shawn-Yu Lin/Rensselaer Polytechnic Institute