World's Lightest Solid Is Lighter Than Air

A team of chemical engineers in China has manufactured the lightest solid material ever produced, which they claim will one day play a major role in cleaning up pollution.The material is called a "Graphene Aerogel" and has about one-sixth the density of air. It’s also extremely absorbent, capable of soaking up to 900 times its own weight.This quality makes it a potentially invaluable tool for environmental cleanup efforts, says Gao Chao at Zhejiang University’s Department of Polymer Science and Engineering.“Carbon aerogel is expected to play an important role in pollution control such as oil spill control, water purification and even air purification,” Gao says.Aerogels are extremely light synthetic materials, created by removing all the liquid from a gel and replacing it with gas.This particular aerogel, made of carbon nanotubes and graphene, was also freeze-dried by the Zhejiang research team.The process was used to remove all moisture from the aerogel, making the material much lighter than any aerogel ever created before while preserving its structural integrity and strength.“When an aerogel the size of a mug is put on slender setaria grass, its blades do not bend," Gao said.Another major advantage of the freeze-drying process, says Gao, is that it will make mass production of the aerogel significantly simpler and more cost-effective.