By Tushna Commissariat
Two teams of researchers in Germany have fabricated a material that they say is the lightest in the world. Aerographite – as the researchers have dubbed it – is a 3D network of porous carbon nanotubes and weighs only 0.2 mg per cubic centimetre, making it 75 times lighter than Styrofoam. Nevertheless, the researchers say that it is very strong and can withstand large amounts of compression (up to 95%) and tension loads. This is one of its many unique features, as most lightweight materials can easily be compressed but become weak when exposed to large amounts of stress. Aerographite, on the other hand, becomes more solid (up to a certain point) when compressed, making it stronger.
The researchers at Kiel University and Hamburg University of Technology, both in Germany, say that aerographite is jet-black, stable, electrically conductive, ductile and non-transparent, and has a very low density thanks to the fact that it is composed of hollow carbon nanotubes. Aerographite weights four times less than the hitherto lightest material in the world – a nickel material that was revealed only six months ago. The scanning-electron-microscope image above shows the hollow carbon tubes that form a fine mesh.
The researchers say that aerographite could have innumerable applications – it could be used to make lightweight lithium-ion batteries, to build satellites and even in water-purification systems.