MIT engineers have cooked up a material that’s 10 times blacker than anything else previously reported. Capturing more than 99.995 percent of any incoming light, the material is made of vertically aligned carbon nanotubes (CNTs) grown on chlorine-etched aluminum foil. And it was discovered by accident.
The researchers had actually been experimenting with ways to grow CNTs on electrically conductive materials — such as aluminum — to boost their electrical and thermal properties. The color of the resulting material surprised the team, and they only realized what they had invented after they measured its optical reflectance.
According to Brian Wardle, professor of aeronautics and astronautics at MIT, it could be used in optical blinders that reduce unwanted glare, to help space telescopes spot orbiting exoplanets.