German Scientists Create Aerographite, the Lightest Material in the World
Posted on July 17, 2012
A network of porous carbon tubes that is three-dimensionally interwoven at the nano and micro level is the lightest material in the world. The substance weighs just 0.2 milligrams per cubic centimeter. It is 75 times lighter than Styrofoam.
Scientists of Kiel University (KU) and Hamburg University of Technology (TUHH) named their joint creation aerographite. The researchers describe aerographite as "jet black, remains stable, is electrically conductive, ductile and non-transparent."
Matthias Mecklenburg, co-author and Ph.D. student at the TUHH says, "Think of the Aerographite as an ivy-web, which winds itself around a tree. And than take away the tree."
To create the material, researchers started with a zinc oxide in powder form and heated it up to 900 degrees Celsius, which transformed it into a crystalline form. From this material the scientists made a kind of pill. In it, the zinc-oxide formed micro and nano structues, called tetrapods. These interweave and construct a stable entity of particles that form the porous pill. The tetrapods produced the network that is the basis for Aerographite. In a next step, the pill is positioned into the reactor for chemical vapour deposition at TUHH and heated up to 760 degrees Celsius.
Hamburg's Professor Karl Schulte says, "In a streaming gas atmosphere that is enriched with carbon, the zinc oxide is being equipped with a graphite coating of only a few atomic layers. This forms the tanged-web structures of the Aerographite. Simultaneously, hydrogen is introduced. It reacts with the oxygen in the zinc oxide and results in the emission of steam and zinc gas."
The very small masses of the aerographite allow quick changes of direction. This video shows aerographite jumping onto a plastic pole and back onto the table. The aerographite gets electric charge from the pole and then emits it to the table.
