Last November, we told you about a metallic microlattice that was light enough to rest on the seed heads of a dandelion. At the time, it had just supplanted NASA's aerogel as the lightest material on Earth by a mere tenth of a milligram per cubic centimeter (the former has a density of just .9 mg/cm3; the latter an even 1 mg/cm3.)
Now, researchers at the Hamburg University of Technology have created a material that beats out both of these ultralight substances handily. They call it Aerographite, and it has a density of less than 0.2 mg/cm3. The researchers grow the material through a novel twist on a synthesis technique known as chemical vapor deposition, a process which gives rise to a network of ethereal-looking, yet surprisingly resilient, hollow carbon microtubes.
"Despite its low density," write the researchers in the latest issue of Advanced Materials, "the [Aerographite's] design leads to remarkable mechanical, electrical, and optical properties. The first experiments with Aerographite electrodes confirm its applicability." According to New Scientist, the material's structure allows it to be compressed "by a factor of a thousand, only to spring back to its original size" — a property it shares with the world's now second-lightest material.