Mar. 19, 2013
Scientists at Zhejiang University have developed a kind of ultra-light material called carbon aerogel. This solid material has a density of only 0.16 mg/cubic centimeter, one sixth of that of the air. It’s the world’s lightest material so far.
Aerogel is a material produced with semi-solid gel dried and solvent removed. It appears in a solid state with many internal pores filled with air, and thus it’s of minimal desity. Prof. Gao Chao’s research team freeze-dried solutions of carbon nanotubes and graphene to remove moisture and retain integrity, and produced the aerogel that broke the record of the world’s lightest material. The previous world record holder was graphite aerogel produced by German scientists in 2012 with 0.18 mg/cubic centimeter.
"Carbon aerogel is similar to carbon sponge in structure. When an aerogel of the size of a mug is put on Setaria, the slender grass will not bend.” Gao Chao said.
Despite its fragile appearance, carbon aerogel is excellent in elasticity. It can bounce back when compressed. In addition, it’s one of the materials with biggest oil absorption capacity. Current oil absorbing products can usually absorb organic solvent of about 10 times of their own weight. The carbon aerogel newly developed can absorb up to 900 times their own weight.
A related paper was published online in Advanced Materials on February 18, and was published in the “Research Highlights” column in Nature. “Carbon aerogel is expected to play an important role in pollution control such as oil spill control, water purification and even air purification.” Gao Chao said that the traditional production method of aerogels could not meet the needs of mass production. However, their freeze-drying approach makes the aerogel production process more convenient and makes it possible for mass production and application.
Now the team is conducting further research on the absorption performance and application of the aerogel. In addition to pollution control, carbon aerogel is expected to become an ideal material for energy storage insulation, catalytic carrier and sound-absorption.