Aerographene

Aerographene or graphene aerogel is, as of March 2013, the least dense solid known, at 160 g/m3 (0.0100 lb/cu ft), less than helium. It is approximately 7.5 times less dense than air (The cited density does not include the weight of the air incorporated in the structure: it does not float in air). It was developed at Zhejiang University. Allegedly the material can be produced at the scale of cubic meters. Aerographene or graphene aerogel is, as of March 2013, the least dense solid known, at 160 g/m3 (0.0100 lb/cu ft), less than helium. It is approximately 7.5 times less dense than air (The cited density does not include the weight of the air incorporated in the structure: it does not float in air). It was developed at Zhejiang University. Allegedly the material can be produced at the scale of cubic meters. Aerographene contains carbon nanotube supports on the inside. These are surrounded by a graphene exterior. Aerographene is an elastic foam. Its density is such that blocks of it can be balanced on small plants and plant structures such as flowers and grasses and it is considered the least dense solid ever made. Aerographene was discovered at Zhejiang University by a team of scientists led by Gao Chao. He and his team had already successfully created macroscopic materials made out of graphene. These materials were one-dimensional and two-dimensional. However, when synthesizing aerographene, the scientists instead created a three-dimensional structure. The synthesis was accomplished by the freeze-drying of carbon nanotube solutions and large amounts of graphene oxide. Residual oxygen was then removed chemically. One method employs freeze drying that can yield graphene sponges of arbitrary size. As of 2013, however, aerographene is usually produced in amounts on the order of cubic centimeters. Aerographene has potential applications for cleaning up oil spills, due to its ability to absorb 900 times its weight in oil. It can also be used to gather dust from the tails of comets.