A new class of nanostructures

Author: William Gilroy

Researchers from the University of Notre Dame and Argonne National Laboratory have discovered a new class of materials that may provide a better understanding of how radioactive materials behave in the environment.

“No one has ever seen anything like these,” says Peter Burns, chairman of Notre Dame’s Department of Civil Engineering and Geological Sciences. Called actinyl peroxide compounds, the materials self-assemble into unbelievably small hollow cages that could have useful new electronic, magnetic and structural properties important to the emerging world of nanotechnology.

The new materials form from uranium and neptunium-peroxide solutions at room temperature. They consist of groups of 24, 28 or 32 identical polyhedra that are linked into clusters measuring about two nanometers—billionths of a meter—in diameter.

Burns and his Argonne Lab colleague, Lynda Soderholm, believe that these actinyl nanospheres may form in alkaline mixtures of nuclear waste, such as at the high-level nuclear waste tanks found at Hanford, Washington, the site of nine nuclear reactors. Knowledge of the new material is especially important for the Yucca Mountain repository (see accompanying interview).

Burns and Soderholm plan to focus on the self-assembling aspect of these materials. Reproducible, self-assembling nanostructures are the current Holy Grail in the nanotechnology world. When they can be manufactured, industry hopes to use them as catalysts, computer chips, solar cells, flexible batteries and data storage devices.