ARGONNE, Ill., March 2 (UPI) -- U.S. scientists say they've created a material that mimics a Venus Flytrap, but instead of catching insects, it traps radioactive nuclear waste.
Mercouri Kanatzidis, a scientist at the Argonne National Laboratory in Illinois, and Nan Ding, a chemist at Northwestern University, said their sulfide framework can trap radioactive cesium ions, giving it the potential of helping speed clean-up of nuclear waste.
The researchers said nuclear waste contains both non-toxic sodium ions and highly radioactive cesium isotopes and most materials don't distinguish between the two.
Kanatzidis said the newly developed material is composed of metal sulfides with a negative charge. Its pores, therefore, attract positively charged ions, making it a good candidate for ion exchange. When immersed in a solution with other positive ions, the ions tucked inside the pores switch places with the ions outside.
Sodium ions do that freely, Kanatzidis said. But when the researchers filled the material with cesium ions, they found those ions refused to move from the material.
"Imagine the framework like a Venus flytrap," Kanatzidis said. "When the plant jaws are open, you can drop a pebble in and the plant won't close -- it knows it isn't food. When a fly enters, however, the plant's jaws snap shut.
"As far as we know, this Venus-flytrap process is unique," Kanatzidis added. "It also works over a large range of acidities.
The research appears in the journal Nature Chemistry.
