• Number 377  |
• December 3, 2012

New nano trap protects environment

A new type of nanoscale molecular trap makes it possible for industry to store large amounts of hydrogen in small fuel cells or capture, compact and remove volatile radioactive gas from spent nuclear fuel in an affordable, easily commercialized way.

The ability to adjust the size of the trap openings to select for specific molecules or to alter how molecules are released at industrially accessible pressures makes the trap uniquely versatile.  The trap is constructed of commercially available material and made possible through collaborative work at DOE's Argonne and Sandia national laboratories.

"This introduces a new class of materials to nuclear waste remediation," said Tina Nenoff, a chemist at Sandia National Laboratories. "This design can capture and retain about five times more iodine that current material technologies."

Organic molecules linked together with metal ions in a molecular-scale Tinker Toy-like lattice called a metal-organic-framework, or MOF, form the trap. Molecules of radioactive iodine or carbon dioxide or even hydrogen for use as fuel can enter through windows in the framework.

Once pressure is applied, these windows are distorted, preventing the molecules from leaving.  This creates a cage and a way of selecting what to trap based on the molecule's shape and size.

[Jared Sagoff, 630.252.5549,
jsagoff@anl.gov]