World's lightest material created

HANGZHOU, China, March 22 (UPI) -- Chinese scientists say they have developed the world's lightest material, lighter than air, which could play an important role in tackling pollution.

The material -- dubbed graphene aerogel or carbon aerogel, and developed at Zhejiang University in Hangzhou -- weighs 0.16 milligrams per cubic centimeter, a sixth the weight of air, China's official Xinhua News Agency reported Friday.

The material, derived from a gel with the liquid component replaced by a gas, is easy to manufacture and has strong oil-absorption properties, its developer says.

"Carbon aerogel is expected to play an important role in pollution control such as oil spill control, water purification and even air purification," Zhejiang researcher Gao Chao said.

Current oil-absorbent products can absorb about 10 times their own weight in organic solvents. The newly developed carbon aerogel can absorb up to 900 times its own weight, researchers said.

Aerogels were first created in the early 1930s. In 1999 NASA used a silicon-based aerogel in a spacecraft to return dust samples after the probe, dubbed Stardust, passed through a comet's tail.

Gao and his research team produced the aerogel using a freeze-dried process that removed moisture from carbon nanotubes but retained their integrity, creating what is now believed to be the world's lightest material.

When a piece of aerogel the size of a coffee mug was placed on top of slender blades of grass, the blades did not blend, the researchers said.