aerographite

thumb|Internal structure of a 'closed-graphitic-shell' aerographite (scanning electron microscopy|SEM image) Aerographite is a synthetic foam consisting of a porous interconnected network of tubular carbon. With a density of 180 g/m3 it is one of the lightest structural materials ever created. It was developed jointly by a team of researchers at the University of Kiel and the Technical University of Hamburg in Germany, and was first reported in a scientific journal in June 2012.

==Structure and properties== Aerographite is a black freestanding material that can be produced in various shapes occupying a volume of up to several cubic centimeters. It consists of a seamless interconnected network of carbon tubes that have micron-scale diameters and a wall thickness of about 15 nm. Because of the relatively lower curvature and larger wall thickness, these walls differ from the graphene-like shells of carbon nanotubes and resemble vitreous carbon in their properties. These walls are often discontinuous and contain wrinkled areas that improve the elastic properties of aerographite. The carbon bonding in aerographite has an sp2 character, as confirmed by electron energy loss spectroscopy and electrical conductivity measurements. Upon external compression, the conductivity increases, along with material density, from ~0.2 S/m at 0.18 mg/cm3 to 0.8 S/m at 0.2 mg/cm3. The conductivity is higher for a denser material, 37 S/m at 50 mg/cm3.