Just in time for Halloween, scientists have developed the blackest material – a material so dark that it absorbs almost all the light that hits its surface.
The new material, developed by researchers from Saudi Arabia’s King Abdulla University of Science and Technology, is built from carbon nanotubes – in fact, a series of small nanoparticle spheres, each with an nano-cylinder on top. The result is a material that absorbs 98 to 99 percent of light in the spectrum between 400 and 1,400nm – which is more than the human eye can even see. A typical human eye will respond to wavelengths from about 390 to 700 nm.
This sphere absorbs 26% more light than any other known material, from every angle. The applications for this technology are very important, ranging from solar panels to optical communication.
“Engineering broadband light absorbers is crucial to many applications, including energy-harvesting devices and optical interconnects. The performances of an ideal absorber are that of a black body, a dark material that absorbs radiation at all angles and polarizations,” researchers write in the study.
Rather interestingly, the idea for this technology came from a white cyphochilus beetle. Cyphochilus is a genus of beetle with unusually bright white scales on the body, generally found in southeast Asia. The whiteness of the scales is caused by a thin layer of a highly reflective natural photonic solid in its scales, though the exoskeleton of the beetle underneath the scales is black. The team tried to replicate that technology, and instead of avoiding light, absorb it.
“The material comprises nanoparticles composed of a nanorod with a nanosphere of 30 nm diameter attached. When diluted into liquids, a small concentration of nanoparticles absorbs on average 26% more than carbon nanotubes, the darkest material available to date,” they conclude.
Journal Referece: Jianfeng Huang, Changxu Liu, Yihan Zhu, Silvia Masala, Erkki Alarousu, Yu Han & Andrea Fratalocchi. Harnessing structural darkness in the visible and infrared wavelengths for a new source of light. Nature Nanotechnologydoi:10.1038/nnano.2015.228
