'Nanopaper' Made to Soak Up Oil Spills

May 30, 2008 -- It looks like paper. It feels like paper. It's even made like paper. But this paper, made from metal nanowires, can sit in water for months and never get wet, while soaking up to 20 times its weight in oil.

"You can even print on it and cut it just like paper," said Jing Kong, a researcher at the Massachusetts Institute of Technology and co-author of a study on the paper appearing in this month's issue of Nature Nanotechnology.

The new nanopaper is designed to help clean oil spills, even difficult emulsions, and other environmental toxins.

The nanopaper is made from solid potassium manganese oxide nanowires instead of cellulose, the main ingredient of normal paper. Each nanowire is about 20 nanometers in diameter, and together they naturally clump together to form strands several centimeters long.

After being dissolved in water, the nanometers dry rapidly to create a sheet of nanopaper.

"The process of making the nanopaper is same one you would use to make [normal] paper," said Francesco Stellacci, a study co-author also at MIT.

By itself, the nanopaper sucks up water just like normal paper. But by coating the nanopaper with siloxane vapor, a common polymer, the researchers turned it from a super hydrophilic material into a super hydrophobic material, repelling water while attracting oil.